Linear ACT-21A Key Ring Transmitter 1-Channel (Qty 10) Doorking In-Ground Opener Photo Eye is required or

Photo Eye is required or this control panel with not function

The lower current requirement means smaller solar panels are needed

UL-325 Compliant

jumper selection

1 - 33 amp hour batteries

Linear ACT-21A Key Ring Transmitter 1-Channel (Qty 10) Doorking In-Ground Opener Photo Eye is required orCLICK HERE FOR MANUAL ACT 21A 1 Channel Key Ring Transmitter ***Sold in multiples of 10 only*** The Linear ACT 21A 1 Channel Key Ring Transmitter is designed for use with Linear access control products. The Linear ACT 21A is a single channel device supplied with a quick disconnect key ring. Also included are lithium batteries with a five year service life. A unique 10 second timeout feature prevents the system from being shut down by a single