diff --git a/src/descriptor.c b/src/descriptor.c
index 096c8ee..83fd3a9 100644
--- a/src/descriptor.c
+++ b/src/descriptor.c
@@ -307,6 +307,10 @@ static const dc_descriptor_t g_descriptors[] = {
 	{"Mares", "Smart Air",         DC_FAMILY_MARES_ICONHD , 0x24, DC_TRANSPORT_SERIAL | DC_TRANSPORT_BLE, dc_filter_mares},
 	{"Mares", "Quad",              DC_FAMILY_MARES_ICONHD , 0x29, DC_TRANSPORT_SERIAL | DC_TRANSPORT_BLE, dc_filter_mares},
 	{"Mares", "Horizon",           DC_FAMILY_MARES_ICONHD , 0x2C, DC_TRANSPORT_SERIAL, NULL},
+	{"Mares", "Puck Air 2",        DC_FAMILY_MARES_ICONHD , 0x2D, DC_TRANSPORT_BLE, dc_filter_mares},
+	{"Mares", "Sirius",            DC_FAMILY_MARES_ICONHD , 0x2F, DC_TRANSPORT_BLE, dc_filter_mares},
+	{"Mares", "Quad Ci",           DC_FAMILY_MARES_ICONHD , 0x31, DC_TRANSPORT_BLE, dc_filter_mares},
+	{"Mares", "Puck 4",            DC_FAMILY_MARES_ICONHD , 0x35, DC_TRANSPORT_BLE, dc_filter_mares},
 	/* Heinrichs Weikamp */
 	{"Heinrichs Weikamp", "OSTC",     DC_FAMILY_HW_OSTC, 0, DC_TRANSPORT_SERIAL, NULL},
 	{"Heinrichs Weikamp", "OSTC Mk2", DC_FAMILY_HW_OSTC, 1, DC_TRANSPORT_SERIAL, NULL},
@@ -706,6 +710,9 @@ dc_filter_mares (dc_descriptor_t *descriptor, dc_transport_t transport, const vo
 	static const char * const bluetooth[] = {
 		"Mares bluelink pro",
 		"Mares Genius",
+		"Sirius",
+		"Quad Ci",
+		"Puck4",
 	};
 
 	if (transport == DC_TRANSPORT_BLE) {
diff --git a/src/device.c b/src/device.c
index ff6a198..a7e60b7 100644
--- a/src/device.c
+++ b/src/device.c
@@ -176,7 +176,7 @@ dc_device_open (dc_device_t **out, dc_context_t *context, dc_descriptor_t *descr
 		rc = mares_darwin_device_open (&device, context, iostream, dc_descriptor_get_model (descriptor));
 		break;
 	case DC_FAMILY_MARES_ICONHD:
-		rc = mares_iconhd_device_open (&device, context, iostream);
+		rc = mares_iconhd_device_open (&device, context, iostream, dc_descriptor_get_model (descriptor));
 		break;
 	case DC_FAMILY_HW_OSTC:
 		rc = hw_ostc_device_open (&device, context, iostream);
diff --git a/src/mares_iconhd.c b/src/mares_iconhd.c
index db6d20b..c968685 100644
--- a/src/mares_iconhd.c
+++ b/src/mares_iconhd.c
@@ -48,6 +48,10 @@
 #define SMARTAIR  0x24
 #define QUAD      0x29
 #define HORIZON   0x2C
+#define PUCKAIR2  0x2D
+#define SIRIUS    0x2F
+#define QUADCI    0x31
+#define PUCK4     0x35
 
 #define ISSMART(model) ( \
 	(model) == SMART || \
@@ -56,10 +60,25 @@
 
 #define ISGENIUS(model) ( \
 	(model) == GENIUS || \
-	(model) == HORIZON)
+	(model) == HORIZON || \
+	(model) == PUCKAIR2 || \
+	(model) == SIRIUS || \
+	(model) == QUADCI || \
+	(model) == PUCK4)
+
+#define ISSIRIUS(model) ( \
+	(model) == PUCKAIR2 || \
+	(model) == SIRIUS || \
+	(model) == QUADCI || \
+	(model) == PUCK4)
 
 #define MAXRETRIES 4
 
+#define MAXPACKET 244
+
+#define FIXED    0
+#define VARIABLE 1
+
 #define ACK 0xAA
 #define END 0xEA
 #define XOR 0xA5
@@ -104,6 +123,7 @@ typedef struct mares_iconhd_device_t {
 	unsigned char version[140];
 	unsigned int model;
 	unsigned int packetsize;
+	unsigned int ble;
 } mares_iconhd_device_t;
 
 static dc_status_t mares_iconhd_device_set_fingerprint (dc_device_t *abstract, const unsigned char data[], unsigned int size);
@@ -171,6 +191,10 @@ mares_iconhd_get_model (mares_iconhd_device_t *device)
 		{"Smart Air",   SMARTAIR},
 		{"Quad",        QUAD},
 		{"Horizon",     HORIZON},
+		{"Puck Air 2",  PUCKAIR2},
+		{"Sirius",      SIRIUS},
+		{"Quad Ci",     QUADCI},
+		{"Puck4",       PUCK4},
 	};
 
 	// Check the product name in the version packet against the list
@@ -187,10 +211,11 @@ mares_iconhd_get_model (mares_iconhd_device_t *device)
 }
 
 static dc_status_t
-mares_iconhd_packet (mares_iconhd_device_t *device,
+mares_iconhd_packet_fixed (mares_iconhd_device_t *device,
 	unsigned char cmd,
 	const unsigned char data[], unsigned int size,
-	unsigned char answer[], unsigned int asize)
+	unsigned char answer[], unsigned int asize,
+	unsigned int *actual)
 {
 	dc_status_t status = DC_STATUS_SUCCESS;
 	dc_device_t *abstract = (dc_device_t *) device;
@@ -262,15 +287,120 @@ mares_iconhd_packet (mares_iconhd_device_t *device,
 		return DC_STATUS_PROTOCOL;
 	}
 
+	if (actual) {
+		*actual = asize;
+	}
+
 	return DC_STATUS_SUCCESS;
 }
 
 static dc_status_t
-mares_iconhd_transfer (mares_iconhd_device_t *device, unsigned char cmd, const unsigned char data[], unsigned int size, unsigned char answer[], unsigned int asize)
+mares_iconhd_packet_variable (mares_iconhd_device_t *device,
+	unsigned char cmd,
+	const unsigned char data[], unsigned int size,
+	unsigned char answer[], unsigned int asize,
+	unsigned int *actual)
+{
+	dc_status_t status = DC_STATUS_SUCCESS;
+	dc_device_t *abstract = (dc_device_t *) device;
+	unsigned char packet[MAXPACKET] = {0};
+	size_t length = 0;
+
+	if (device_is_cancelled (abstract))
+		return DC_STATUS_CANCELLED;
+
+	// Send the command header to the dive computer.
+	const unsigned char command[2] = {
+		cmd, cmd ^ XOR,
+	};
+	status = dc_iostream_write (device->iostream, command, sizeof(command), NULL);
+	if (status != DC_STATUS_SUCCESS) {
+		ERROR (abstract->context, "Failed to send the command header.");
+		return status;
+	}
+
+	// Read either the entire data packet (if there is no command data to send),
+	// or only the header byte (if there is also command data to send).
+	status = dc_iostream_read (device->iostream, packet, sizeof (packet), &length);
+	if (status != DC_STATUS_SUCCESS) {
+		ERROR (abstract->context, "Failed to receive the packet header.");
+		return status;
+	}
+
+	if (size) {
+		// Send the command payload to the dive computer.
+		status = dc_iostream_write (device->iostream, data, size, NULL);
+		if (status != DC_STATUS_SUCCESS) {
+			ERROR (abstract->context, "Failed to send the command data.");
+			return status;
+		}
+
+		// Read the data packet.
+		size_t len = 0;
+		status = dc_iostream_read (device->iostream, packet + length, sizeof (packet) - length, &len);
+		if (status != DC_STATUS_SUCCESS) {
+			ERROR (abstract->context, "Failed to receive the packet data.");
+			return status;
+		}
+
+		length += len;
+	}
+
+	if (length < 2 || length - 2 > asize) {
+		ERROR (abstract->context, "Unexpected packet length (" DC_PRINTF_SIZE ").", length);
+		return DC_STATUS_PROTOCOL;
+	}
+
+	// Verify the header byte.
+	if (packet[0] != ACK) {
+		ERROR (abstract->context, "Unexpected packet header byte (%02x).", packet[0]);
+		return DC_STATUS_PROTOCOL;
+	}
+
+	// Verify the trailer byte.
+	if (packet[length - 1] != END) {
+		ERROR (abstract->context, "Unexpected packet trailer byte (%02x).", packet[length - 1]);
+		return DC_STATUS_PROTOCOL;
+	}
+
+	if (actual == NULL) {
+		// Verify the actual length.
+		if (length - 2 != asize) {
+			ERROR (abstract->context, "Unexpected packet length (" DC_PRINTF_SIZE ").", length - 2);
+			return DC_STATUS_PROTOCOL;
+		}
+	} else {
+		// Return the actual length.
+		*actual = length - 2;
+	}
+
+	memcpy (answer, packet + 1, length - 2);
+
+	return DC_STATUS_SUCCESS;
+}
+
+static dc_status_t
+mares_iconhd_packet (mares_iconhd_device_t *device,
+	unsigned char cmd,
+	const unsigned char data[], unsigned int size,
+	unsigned char answer[], unsigned int asize,
+	unsigned int *actual)
+{
+	dc_transport_t transport = dc_iostream_get_transport (device->iostream);
+
+	if (transport == DC_TRANSPORT_BLE && device->ble == VARIABLE) {
+		return mares_iconhd_packet_variable (device, cmd, data, size, answer, asize, actual);
+	} else {
+		return mares_iconhd_packet_fixed (device, cmd, data, size, answer, asize, actual);
+	}
+}
+
+static dc_status_t
+mares_iconhd_transfer (mares_iconhd_device_t *device, unsigned char cmd, const unsigned char data[], unsigned int size, unsigned char answer[], unsigned int asize, unsigned int *actual)
 {
 	unsigned int nretries = 0;
 	dc_status_t rc = DC_STATUS_SUCCESS;
-	while ((rc = mares_iconhd_packet (device, cmd, data, size, answer, asize)) != DC_STATUS_SUCCESS) {
+	while ((rc = mares_iconhd_packet (device, cmd, data, size, answer, asize, actual)) != DC_STATUS_SUCCESS) {
 		// Automatically discard a corrupted packet,
 		// and request a new one.
 		if (rc != DC_STATUS_PROTOCOL && rc != DC_STATUS_TIMEOUT)
@@ -294,7 +424,9 @@ mares_iconhd_read_object(mares_iconhd_device_t *device, dc_event_progress_t *pro
 	dc_status_t status = DC_STATUS_SUCCESS;
 	dc_device_t *abstract = (dc_device_t *) device;
 	dc_transport_t transport = dc_iostream_get_transport (device->iostream);
-	const unsigned int maxpacket = (transport == DC_TRANSPORT_BLE) ? 124 : 504;
+	const unsigned int maxpacket = (transport == DC_TRANSPORT_BLE) ?
+		(device->ble == VARIABLE ? MAXPACKET - 3 : 124) :
+		504;
 
 	// Update and emit a progress event.
 	unsigned int initial = 0;
@@ -312,7 +444,7 @@ mares_iconhd_read_object(mares_iconhd_device_t *device, dc_event_progress_t *pro
 		subindex & 0xFF
 	};
 	memset (cmd_init + 6, 0x00, sizeof(cmd_init) - 6);
-	status = mares_iconhd_transfer (device, CMD_OBJ_INIT, cmd_init, sizeof (cmd_init), rsp_init, sizeof (rsp_init));
+	status = mares_iconhd_transfer (device, CMD_OBJ_INIT, cmd_init, sizeof (cmd_init), rsp_init, sizeof (rsp_init), NULL);
 	if (status != DC_STATUS_SUCCESS) {
 		ERROR (abstract->context, "Failed to transfer the init packet.");
 		return status;
@@ -366,13 +498,21 @@ mares_iconhd_read_object(mares_iconhd_device_t *device, dc_event_progress_t *pro
 		}
 
 		// Transfer the segment packet.
+		unsigned int length = 0;
 		unsigned char rsp_segment[1 + 504];
-		status = mares_iconhd_transfer (device, cmd, NULL, 0, rsp_segment, len + 1);
+		status = mares_iconhd_transfer (device, cmd, NULL, 0, rsp_segment, len + 1, &length);
 		if (status != DC_STATUS_SUCCESS) {
 			ERROR (abstract->context, "Failed to transfer the segment packet.");
 			return status;
 		}
 
+		if (length < 1) {
+			ERROR (abstract->context, "Unexpected packet length (%u).", length);
+			return DC_STATUS_PROTOCOL;
+		}
+
+		length--;
+
 		// Verify the packet header.
 		if ((rsp_segment[0] & 0xF0) >> 4 != toggle) {
 			ERROR (abstract->context, "Unexpected packet header (%02x).", rsp_segment[0]);
@@ -380,12 +520,12 @@ mares_iconhd_read_object(mares_iconhd_device_t *device, dc_event_progress_t *pro
 		}
 
 		// Append the payload to the output buffer.
-		if (!dc_buffer_append (buffer, rsp_segment + 1, len)) {
+		if (!dc_buffer_append (buffer, rsp_segment + 1, length)) {
 			ERROR (abstract->context, "Insufficient buffer space available.");
 			return DC_STATUS_NOMEMORY;
 		}
 
-		nbytes += len;
+		nbytes += length;
 		npackets++;
 
 		// Update and emit the progress events.
@@ -399,7 +539,7 @@ mares_iconhd_read_object(mares_iconhd_device_t *device, dc_event_progress_t *pro
 }
 
 dc_status_t
-mares_iconhd_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_t *iostream)
+mares_iconhd_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_t *iostream, unsigned int model)
 {
 	dc_status_t status = DC_STATUS_SUCCESS;
 	mares_iconhd_device_t *device = NULL;
@@ -422,9 +562,10 @@ mares_iconhd_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_
 	memset (device->version, 0, sizeof (device->version));
 	device->model = 0;
 	device->packetsize = 0;
+	device->ble = ISSIRIUS(model) ? VARIABLE : FIXED;
 
 	// Create the packet stream.
-	if (transport == DC_TRANSPORT_BLE) {
+	if (transport == DC_TRANSPORT_BLE && device->ble == FIXED) {
 		status = dc_packet_open (&device->iostream, context, iostream, 244, 20);
 		if (status != DC_STATUS_SUCCESS) {
 			ERROR (context, "Failed to create the packet stream.");
@@ -467,7 +608,7 @@ mares_iconhd_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_
 
 	// Send the version command.
 	status = mares_iconhd_transfer (device, CMD_VERSION, NULL, 0,
-		device->version, sizeof (device->version));
+		device->version, sizeof (device->version), NULL);
 	if (status != DC_STATUS_SUCCESS) {
 		goto error_free_iostream;
 	}
@@ -479,7 +620,7 @@ mares_iconhd_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_
 	unsigned int memsize = 0;
 	if (device->model == QUAD) {
 		unsigned char rsp_flash[4] = {0};
-		status = mares_iconhd_transfer (device, CMD_FLASHSIZE, NULL, 0, rsp_flash, sizeof (rsp_flash));
+		status = mares_iconhd_transfer (device, CMD_FLASHSIZE, NULL, 0, rsp_flash, sizeof (rsp_flash), NULL);
 		if (status != DC_STATUS_SUCCESS) {
 			WARNING (context, "Failed to read the flash memory size.");
 		} else {
@@ -538,7 +679,7 @@ mares_iconhd_device_open (dc_device_t **out, dc_context_t *context, dc_iostream_
 
 
 error_free_iostream:
-	if (transport == DC_TRANSPORT_BLE) {
+	if (transport == DC_TRANSPORT_BLE && device->ble == FIXED) {
 		dc_iostream_close (device->iostream);
 	}
 error_free:
@@ -551,9 +692,10 @@ static dc_status_t
 mares_iconhd_device_close (dc_device_t *abstract)
 {
 	mares_iconhd_device_t *device = (mares_iconhd_device_t *) abstract;
+	dc_transport_t transport = dc_iostream_get_transport (device->iostream);
 
 	// Close the packet stream.
-	if (dc_iostream_get_transport (device->iostream) == DC_TRANSPORT_BLE) {
+	if (transport == DC_TRANSPORT_BLE && device->ble == FIXED) {
 		return dc_iostream_close (device->iostream);
 	}
 
@@ -601,7 +743,7 @@ mares_iconhd_device_read (dc_device_t *abstract, unsigned int address, unsigned
 			(len >>  8) & 0xFF,
 			(len >> 16) & 0xFF,
 			(len >> 24) & 0xFF};
-		rc = mares_iconhd_transfer (device, CMD_READ, command, sizeof (command), data, len);
+		rc = mares_iconhd_transfer (device, CMD_READ, command, sizeof (command), data, len, NULL);
 		if (rc != DC_STATUS_SUCCESS)
 			return rc;
 
diff --git a/src/mares_iconhd.h b/src/mares_iconhd.h
index 1b00c54..a6cb6a8 100644
--- a/src/mares_iconhd.h
+++ b/src/mares_iconhd.h
@@ -32,7 +32,7 @@ extern "C" {
 #endif /* __cplusplus */
 
 dc_status_t
-mares_iconhd_device_open (dc_device_t **device, dc_context_t *context, dc_iostream_t *iostream);
+mares_iconhd_device_open (dc_device_t **device, dc_context_t *context, dc_iostream_t *iostream, unsigned int model);
 
 dc_status_t
 mares_iconhd_parser_create (dc_parser_t **parser, dc_context_t *context, const unsigned char data[], size_t size, unsigned int model);
diff --git a/src/mares_iconhd_parser.c b/src/mares_iconhd_parser.c
index 223d7f8..855008a 100644
--- a/src/mares_iconhd_parser.c
+++ b/src/mares_iconhd_parser.c
@@ -45,6 +45,10 @@
 #define QUADAIR   0x23
 #define SMARTAIR  0x24
 #define HORIZON   0x2C
+#define PUCKAIR2  0x2D
+#define SIRIUS    0x2F
+#define QUADCI    0x31
+#define PUCK4     0x35
 
 #define ISSMART(model) ( \
 	(model) == SMART || \
@@ -53,7 +57,11 @@
 
 #define ISGENIUS(model) ( \
 	(model) == GENIUS || \
-	(model) == HORIZON)
+	(model) == HORIZON || \
+	(model) == PUCKAIR2 || \
+	(model) == SIRIUS || \
+	(model) == QUADCI || \
+	(model) == PUCK4)
 
 #define NGASMIXES_ICONHD 3
 #define NGASMIXES_GENIUS 5