Guardian Telecom Waterproof Teleseal Keypad Curly Cord, Volume Control Handset Features: Shown schedule forums immune to water wetness build-up or wetness build-up or condensation and dust 16 assess destruction secured jewelry box with dirt cover finish Solid professional amount control smartphone on models 10/30/40 Deterioration and destruction tolerant steel hardware Electret disruption reducing microphone Eye-catching reed hook-switch decreases moving parts subject to wear Service temperature range from -40 to +60 C (-40 to +140 F)