The shell is fired from the 7.5 cm light infantry howitzer (7,5 cm l.I.G. 18) and is fitted with the l.Igr.Z. 23 n.A. fuze. The colour of the shell is the normal deep olive green with the letters "Al" marked in black 2.4 inch lettering at two position round the shell, midway between the driving band and the shoulder. This marking indicates the inclusion of alumi-nium powder in the filling. The nature of the filling is indicated by the numeral "15" pain-ted near the head of the shell. This is also in black. The overall length of the fuzed shell is 13 inches and the weight, filled and fuzed, is 12 lb. 2 oz. The single narrow driving band is of copper.

The shell is comparatively thin walled and is in two parts, the body and the head. The head is screwed into the body and is threaded internally to receive the fuze and a disc carrying the steel exploder container. The weight of the empty shell is approximately 9 lb. 12 oz.

The bursting charge consists of 1 lb. 7 oz. 4 1/2 dr. of cast T.N.T./aluminium, 90/10, with a density of 1.63. The aluminium powder passes the 240 B.S.S. The exploder cavity formed in the filling is deeper than is required to accommodate the exploder container and is unoccupied to a depth of 2.8 cm below the base of the container. The dimensions of this space correspond with those of the No. 7 smoke box (Rauchentwickler Nr. 7) which is used below the exploder container in amatol-filled shell for this equipment. The addition of the aluminium gives rise to a very considerable evolution of heat and so in-creases the available energy of the explosive. The duration of the flash is also consider-ably prolonged.

The gaine, carried in the exploder container, is the gr.Zdlg. C/98 Np. This is the larger size of the C/98 gaine, filled P.E.T.N./wax, of which details are given in Pamphlet No. 6.

The fuze has optional delay of 0.15 seconds. A description is given in Pamphlet No. 1, page 11. The abbreviated designation stamped on the fuze is l.Igr.Z. 23 n.A.", but on package labels it may be given as "l.Jgr.Z. 23 n.A.".