It had a steel body with carrying hook attached to the side.
The strikerpin was held in position , and a creep spring held it from the primer.
When the safety pin was pulled and the grenade was thrown, the striker was released and would ignite the primer on impact, detonating the grenade.
A defensive model was issued with a 1913 kugelgrenade which was screwed on using a small brass adapter. The mechanism was the same as the offensive type. I have no idea if the 1915 kugelgrenade was used too.

Length 360mm, diameter 70mm (offensive type)

The two photos below show the details of the "kugel" stickgrenade. The connection ring seems to be the same as the normal type, but with a brass igniter fitted in the centre. When the primer was struck by the firingpin, on impact, the flash would ignite the black powder charge.