The following are the specifications for the VS-3 bluetooth© headset as used with the UT133 bluetooth unit:
| Frequency Range | 2402～2480MHz |
| Modulation method | GFSK，π/4-DQPSK，8DPSK |
| Transmission output | Class 1 |
| Carrier spacing | 1MHz |
| Max number of paired Bluetooth devices | 7 devices. You can pair with up to 7 headsets and data devices. The 7 paired devices cannot be all headsets or all data devices. |
| Number of channels | 79 |
| Bluetooth version | 3.0 |
| Supported Profiles | HFP，HSP，A2DP，AVRCP |
| Operating Temperature Range | -20～60℃ |
| Charging Temperature Range | 0～45℃ |
| Power Supply | Nominal 3.7V (Internal battery); External input: 5V±10% (charging) |
| Current Drain | Less than 50mA |
| Dark Current | Less than 5μA |
| External Connector Type | Micro USB |
| Dimensions (w/o projections) | 28.2(W)x65.1(H)x17.8(D) mm |
| Weight | 30g |
| Power Class | Class 1 |
| Output Power | 4.2mW (0.9mW～5.0mW) F1D, Packet : DH5 4.2mW (0.9mW～5.0mW) G1D, Packet : 2-DH5, 3-DH5 |
| Frequency Tolerance | ±75kHz |
| Audio load impedance | more than 16Ω (Standard earbuds range from 16 to 100 ohms) |
| Audio output | less than 150mVrms (32Ω load) |
| Charge Voltage | 4.15 - 4.22V |
| Charge time (USB) | Approx 3Hrs |
| Talk Time | 7Hrs full duty cycle, 10Hrs at 10:10:80 |