Four button transmitter module from QK180 kit. Receiver module also available as QA16RX.

This is state of the art. Up to 15 Transmitter units can be learnt by one Rx unit.    Press button 1 (the button all by itself) while simultaneously pressing the LEARN tact switch on the main board. You only have to do this briefly for under a second. But note it takes about 15 seconds for the two units to internally connect and recognize each other. During this 15 seconds it seems that one and only one keypress of the Tx unit will be recognised. Just disregard this. Wait the full 15 seconds until the two units have connected. Do not press the LEARN button again. Just wait 15 seconds.

Tx units attached to any Rx unit can be unattached by pressing the LEARN button continuously for 8 seconds. The VALID DATA LED is on during these 8 seconds. As soon as the LED goes off then you know that all Tx units previously recognized by the Rx unit have now been unattached from the Rx unit.

The transmitter module supplied here is fully assembled, tested, with a battery included and ready to go.

Check out these related products:
4 ch. 434 MHz Receiver Module
2 channel UHF Receiver module
2 Button UHF keychain Transmitter