Used on rategic weapon systems(poseidon and trident),nimitz class cvn,kidd clas s ddg,ticonderoga class cg (47), forrestal class cv,wasp class lhd, los angeles class ssn (688),oliver perry class ffg,sturgeon class ssn (637),spruance class dd (963). 0.141" hole diameter color white fed std 595 no. 37875