This is original Walkera bluetooth datalink BT-2401B(FCC), which is suitable for QR X350 Premium.

Features:
Original Walkera factory parts.
Used for connecting the mobile and the RC quadcopter.
Suit for Walkera QR X350 Premium quadcopter.
100% brand new and high quality parts.
Easy to install, good choice for replacing your broken bluetooth datalink.

Specifications:
Brand: Walkera
Item number: Premium-Z-16
Item name: 2.4G Bluetooth Datalink
Suit for: Walkera QR X350 Premium quadcopter
Item dimension: 80 * 47 * 25mm / 3.1 * 1.9 * 1.0in
Antenna Length: 110mm / 4.3in
Weight (with antenna): 107g / 3.8oz

Package information:
Package size: 16 * 12 * 5.5cm / 6.3 * 4.7 * 2.2in
Package weight: 152g / 5.3oz
General box

Package list:
1 * Walkera QR X350 Premium-Z-16 Bluetooth Datalink