This defensive stickgrenade had a body filled with shrapnell.
It's fuze had an impellor which released the strikerpin during flight, the grenade would detonate on impact.
Duds occurred when flight was not long enough and the strikerpin was not fully released.

Total length:370mm , Length body: 80mm
Diameter: 50mm
Weight: 630gram , Filling: 80gram.

Photo below © Paul Spence.