40 homemade hand grenade produced for the Armia Krajowa during World War II in occupied Poland.

It was designed by a former worker of the Rembertów Polish Army munition works, Edward Tymoszak (hence the ET abbreviation).

A screw for the fuse was located in the upper part of the shell.

The grenade was equipped with a contact fuze which functioned on impact with the target.

After 1941 all grenades were marked with an inscription in Russian (Desantnaya Udarnaya Granata 41 - Assault Impact Grenade Mark 41) in order to conceal the real origin of the weapon and ensure the safety of the production facilities.