
The Adapter Booster Mk. IVB is used in the 75mm Chemical Shell Mk II for 75-mm guns. In common with adapter boosters for chemical shell, its function is to break up the shell so that the contents may be released and scattered.
The booster charge consists of approximately 1/2 ounces of tetryl. Some boosters are loaded with half tetryl and half TNT, the tetryl being placed around the fuze socket.
No information about functioning.
Cartridge, 75mm Chemical, Mk 2
TM 9-1904, Ammunition Inspection Guide (1944)