Wireless Security Emergency Reporting Access Control Door & Gate Operators Radio Control Audio / Video Distr New Products Product List Product Manuals Software Downloads Discontinued Products	Access Control > Multi Door Controllers > Telephone Entry with Access Control > Telephone Entry > Residential Telephone Entry > Single Door Controllers > Accessories > Transmitters Keychain ACT-21A: 1-Channel Key Ring Transmitter Single-channel transmitter supplied with a quick-disconnect key ring, MegaCode format ACT-21B: 1-Channel Block Coded Key Ring Transmitter Block coded single-channel transmitter supplied with a quick-disconnect key ring, MegaCode format ACT-22A: 3-Channel Key Ring Transmitter Three-channel transmitter supplied with a quick-disconnect key ring, MegaCode format ACT-22B: 3-Channel Block Coded Key Ring Transmitter Block coded three-channel transmitter supplied with a quick-disconnect key ring, MegaCode format ACT-31B: 1-Channel Block Coded Key Ring Transmitter Block coded one-button, one-channel transmitter supplied with a quick-disconnect key ring, MegaCode format NEW! ACT-31C: 1-Channel Custom Block Coded Key Ring Transmitter Custom block coded one-button, one-channel transmitter supplied with a quick-disconnect key ring, MegaCode format ACT-34B: 4-Channel Block Coded Key Ring Transmitter Block coded four-button, four-channel transmitter supplied with a quick-disconnect key ring, MegaCode format NEW! ACT-34C: 4-Channel Custom Block Coded Key Ring Transmitter Custom block coded four-button, four-channel transmitter supplied with a quick-disconnect key ring, MegaCode format Genie Compatible GT-30: 3-channel Genie Compatible Visor Transmitter Three-button, three-channel rolling code visor transmitter with LED supplied with a visor clip for use with Genie receivers and Linear's RGR receiver GT-31: 3-channel Genie Compatible Key Ring Transmitter Three-button, three-channel rolling code key ring transmitter with LED supplied with a quick-disconnect key ring for use with Genie receivers and Linear's RGR receiver Visor MDT-1A: 1-channel Visor Transmitter or MDT-1B: 1-channel Block Coded Visor Transmitter Two-button, one-channel portable transmitter with high visibility LED supplied with a visor clip for use with Linear's access control receivers MDT-2A: 3-channel Visor Transmitter or MDT-2B: 3-channel Block Coded Visor Transmitter Three-button, three-channel portable transmitter with high visibility LED supplied with a visor clip for use with Linear's access control receivers MDT-4A: 5-channel Visor Transmitter or MDT-4B: 5-channel Block Coded Visor Transmitter Four-button, four-channel portable transmitter with high visibility LED supplied with a visor clip for use with Linear's access control receivers MT-1B: 1-channel Block Coded Visor Transmitter Block coded one-button, one-channel portable transmitter with LED supplied with a visor clip for use with Linear's access control receivers MT-2B: 2-channel Block Coded Visor Transmitter Block coded two-button, two-channel portable transmitter with LED supplied with a visor clip for use with Linear's access control receivers