Firenock is the most advanced lighted nock system on the present market.  Firenock employs both Missile-Arming Technology, which means that they light up once fired, and Surface-Mount Technology (SMT), which means that they do not require any sort of actuator or any pushing and/or twisting to turn on or off (US Patent # 7837580).  Firenock stays lit after hitting hard objects (bone, stone, concrete), if the game is moving vigorously, and even if it is submerged into water for weeks with the Hydro Bow-Fishing Adapter.