Allstar 9931T-318 mhz trinary (+ 0 -) dip switch style garage door opener remote. Made by the linear corporation. 1 button visor sized remote. Features and Specifications Replaces Allstar, Pulsar or Allister brand units model 9931-318 (9 dip switches with 3 position each: +,0,-) 1 Button single channel remote transmitter 318 MHZ Frequency gate or garage door opener Nine (9) 3-positions (trinary) dip switch format