4612 Mini Curtain Door Switch - Up To 3" Travel - Reversible Probe Assembly - Left or Right Installation - Install Probe Top or Bottom - 3?â„¢ Armored Cable Standard - Magnet Mounts in Door Channel - Mounting Hardware Included G.R.I. has solved the curtain door installation problem with the 4612 Curtain Door Series. The 4612 resolves the left or right installation problem plus allows the installer to adapt the install dependant on the application. G.R.I.?â„¢s unique probe design allows the switch to be inserted either from the top of the switch or the bottom allowing access determined by the application