Number of channels: 1/4 Battery: 12V 23A Installation: wireless Wireless transmission distance: 50-150 (m). (open space) Frequency: MAHS40 40.685MHz red buttons. Only Compatible With for MAHS40 40.685MHz for MAHS40-04 Purchase Tips: Check the frequency on the back of the remote control, it must be 40.685MHz. Check the colour of the button, which is red. Check the model number of the remote control, which is MAHS40-04. Programming Manual The transmitter and receiver "understand" each other, the code must be set as follows. Remove the battery cover by sliding it in the direction of the keyring tab. Set the dip switch up/down same as your used remote control or the receiver. Note: Installation guide not included, we strongly recommend you professional installation. Please check as much as possible to make sure the item is what you need. Tips: The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use Colour:Photo Color Material:plastic Package Contents: 1 x Garage Door Remote Control Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.