Precision Timer System Referee Lanyard. Deluxe Referee Lanyard with the PTS adapter, slide adjustment and metal clip. The computer chip of a PTS is tuned to the frequency of the Fox 40, so when it is blown, a microphone and transmitter instantly send the whistle signal to the clock, thereby shutting it off.
Note: Computer chip, belt pack and mini-microphone supplied direct to participating schools by PTS. Fox 40 not included.