Used on kforrestal class cv; virginia class cgn (41); surface minesweeping systems; teletype, model 28; spruance class dd (963); fire control system, missile mk 74 (fcs); kidd class ddg; wasp class lhd; nimitz class cvn. 2a thread class right-hand 1.938" overall length 1.375" overall width weapon system essential unef thread series