▁the ▁head phone ▁jack , ▁similar ▁to ▁the ▁. ▁The ▁ear bud s ▁are ▁similar ▁to ▁the ▁IE 2 ▁head ph ones . ▁A ▁button ▁on ▁the ▁remote ▁label led ▁" A ware ▁Mode " ▁reduces ▁noise - can cellation ▁to ▁let ▁in ▁ambient ▁noise . ▁ ▁Indust rial ▁head ph ones ▁ ▁A 2 0 ▁A viation ▁Head set ▁The ▁" A 2 0 ▁A viation ▁Head set " ▁was ▁released ▁in ▁ 2 0 1 0 ▁as ▁the ▁successor ▁to ▁the ▁" A viation ▁Head set ▁X " ▁( aka ▁A 1 0 ). ▁It ▁has ▁a ▁claimed ▁battery ▁life ▁of ▁ 4 5 ▁hours ▁( using ▁two ▁AA ▁batter ies ) ▁or ▁can ▁be ▁power ed ▁by ▁the ▁air plane ' s ▁elect rical ▁system . ▁There ▁are ▁two ▁versions , ▁one ▁with ▁Bl uetooth ▁and ▁one ▁without . ▁ ▁An ▁updated ▁version ▁of ▁the ▁A 2 0 ▁was ▁released ▁in ▁ 2 0 1 5 . ▁ ▁Com bat ▁Ve h icle ▁C rew man ▁Head set ▁A ▁" Com bat ▁Ve h icle ▁C rew man ▁Head set " ▁was ▁released ▁in ▁ 1 9 9 8 , ▁for ▁use ▁in ▁arm oured ▁vehicles . ▁ ▁Tri port ▁T act ical ▁Head set ▁A ▁" Tri port ▁T act ical ▁Head set " ▁( T TH ) ▁was ▁released ▁in ▁ 2 0 0 4 . ▁It ▁is ▁designed ▁for ▁use ▁in ▁arm oured ▁vehicles ▁and ▁can ▁fit ▁under ▁an ▁inf antry ▁ball istic ▁hel met . ▁An