Title: PIR-21 (Mk165) fuze
Date: 1945
Original Format: photograph: negative
Description: This was a modification of PIR-2 with elements of PIR-19. Distinguishing feature is that the fuze head and rocket motor adapter are made in one piece. About 0.33″ longer than PIR-2 fuzes, apparent in extension of magazine. During March-June 1945 about 50,000 were manufactured and loaded by Caltech.
Collection: Scientific Instruments
Caltech Archives ID: ST-RK-12
