Physical description

Appears to be AN 1993 (Australian Navy) 40MM MK4 Brass Shell fitted with a 4/53 40MM MO MK 4T projectile HES (High explosive substitute) AN (Australian Navy)

Inscriptions & markings

Shell-40MM MK 4, OT28 MF,AN1993. Projectile- HES AN, 40MM MO MK 4T, 0210 4/53 BS