911vehicle Safety Headsets are compatible with most safety vehicle intercoms, allowing the user to select the appropriate detachable cord for their system. 911vehicle Safety Headset models BTH-20 through BTH-60 feature a jack built into each eardome. This feature means instant connectivity to the right or left side without disassembling the headset or bolting and unbolting the headband. These headsets, with detachable cords, permit an affordable alternative to supply each individual with their own headset. All 911vehicle Safety Headsets are certified 24dB NRR without the typical vice-like clamping pressure. Soft acoustic foam ear seals provide comfort and noise attentuation.