Used on engine, aircraft, tf-33-p-7 (c-141a/b); los angeles class ssn (688); level 1 / subsafe; submarine atmosphere control and compressed air/gas; high pressure air system; submarine hydraulic systems; engine, aircraft, tf33-100 (e3a/b/c); engine, aircraft tf33-p-3/5/9 (c/ec-135, b-52h); engine, aircraft tf33-pw-102 (c-135e, ec-135h/k/p). 0.978" center hole diameter