The Jelly Beamer Twist Transmitter is a wireless switch that brings reliable, immediate switch access without the hassle of cords. Multiple Jelly Beamers can be used in the same room at the same time, from as far away as 30-feet, without interference. The 2.5-in/6.4-cm Jelly Beamer also includes an external switch jack, allowing you to use any single switch with our wireless receivers.