PTE-540 (with optional finger PTT) enables clear communication in noisy environments while keeping the ear canal open for situational awareness, featuring a comfortable silica gel-integrated speaker/microphone and a precise, discreet finger PTT. Its Kevlar-reinforced, PU-coated cable boosts durability, making it ideal for use with helmets and masks; it’s suited for firemen, chemical defense personnel, SWAT, policemen and operation forces. Speaker Specification