(1) high sensitivity, good accuracy, effective distance, signal persistence for a long time.
 
(2) the transmitter and receiver for one-to-one encoding, so that its anti-interference ability.
 
(3) the appearance of the remote control material using glass fiber reinforced nylon material, has a strong acid corrosion,
high and low temperature and water and dust resistance.
 
(4) with emergency stop mushroom head, plus two direction function keys.
 
(5) a strong voltage self-test function, when the transmitter voltage is less than 2.2V when the transmitter is slowly flashing
red light tips, the voltage is less than 1.8V transmitter can not work.
 
(6) Up / down can be set to normal, Na jump, whether to suppress each other.

 Model: F21-2D-TX
   outer shell: reinforced nylon
   Weight: about 160 grams
   Protection level: IP64
   Frequency range: UHF 430~440MHz
   Transmitting power: ≤10dBm
   Battery: 2 alkaline 5 batteries (AA)
   Security code: 32 bits (4.3 billion sets of non-repeating identification codes)
   Ambient temperature: -35oC ~ +80 °C (regardless of battery temperature)
   Control distance: no interference 100 meters