The shell casing was molded from cast iron and formed into a pineapple-shaped oval, typical of World War I and II-era hand grenades.

[1] Because of large stocks, it was decided to focus early modernisation efforts at developing a new fuse rather than design the entire grenade for indigenous production.

This was considered a logical choice as a number of Polish companies inherited production lines of German World War I grenade designs.

In 1923 the Department of Arms started a competition for a new fuse that would fit the German M16 and M17 Stielhandgranate hand grenades, the predecessor of the iconic Model 24 .

[2] However, as the field tests proved that the A.C. 23 was prone to malfunction in moist conditions, the Department started a new competition in 1925, again won by Cierpiński's design (A.C.

Eventually the line of fuses led to the final design accepted into Polish service as Zapalnik wz.

31 fuse was considered among the best in the world, soon after its adoption by the Polish Army; both France and Romania bought a license for their production.