12-Кd-ОSТ1 33109-86 / 12-Кд-ОСТ1 33109-86 Crown Nut

12-Кd-ОSТ1 33109-86 / 12-Кд-ОСТ1 33109-86 Crown Nut

12-Кd-ОСТ1 33109-86 is an aviation-grade crown (castellated) nut produced to aerospace standard OST1 33109-86. The crown nut design features slots that accept cotter pins or locking elements, providing positive mechanical locking in critical structural and mechanical assemblies on Mi-8, Mi-17 and Mi-171 helicopters. Manufactured to meet stringent aviation fastener strength, fatigue and dimensional specifications, this crown nut ensures secure retention on drilled bolts under vibration and dynamic loads. Supplied as a certified helicopter airframe hardware component for sale with traceability and documentation available subject to contract.