DS EN 4645-002:2009 Aerospace Series - Connectors, Optical, Circular, Single And Multipin, Coupled By Threaded Ring, Self-Locking 1,25 Mm Diameter Ferrule With Removable Alignment Sleeve Holder - Part 002: Specification Of Performance And Contact Arrangements Describes the performance and contact arrangements of circular optical connectors, coupled by triple start threaded ring.