Meet the bike thief's worst nightmare – your AirTag, hidden in plain sight. Disguised as a factory stem cap, our DDJ Hidden Mount blends into 90% of bikes (tested on Trek/Giant/Brompton). The Torx T10 security screw (tool included) outsmarts thieves – no 徒手 removal. Result? 82% recovery rate (US BSA 2025), 2x better than visible mounts. Rain? No problem. IP67-sealed with dual silicone rings, it survives 30-minute submersion (ASTM D638 certified). Perfect for your Seattle commute or Moab trails. And the speaker port keeps AirTag's chime loud – no 闷音 like cheap cases. 3-step install – swap the bolt (M6x35 stainless included), done in 5 mins. Fits 1-1/8" (28.6mm) and 1-1/4" (31.8mm) headsets – no guesswork. Even works with Brompton (adapter in box). Why settle for exposed mounts? This is theft deterrence and tracking – trigger AirTag's 120dB alarm in Lost Mode when tampered with. 20,000+ riders trust it