Screw (M4), Vacuum Hose Retainer to Power Steering Reservoir, for 90~95 ZR-1, LT5. This is type "B". One is required per engine.
There are 2 types,
(A) reservoir with threaded brass inserts for an M4 machine screw, and
(B) reservoir with no inserts, threads are in plastic holes.
NOTE: This is a USED, GM OEM part.