This spherical grenade project is inspired by the M37 CS smoke grenade. The body can be filled with standard smoke grenade fillers. It uses standard M228 internal parts, the hammer, spring, and pin. This grenade project uses a printable spoon and safety lever, and a printable body. 

The optional rotating safety lever is to be bolted onto the spoon and when in the detent in the forward position the lever will stay in place with the pin pulled as a safety mechanism if the grenade is made to proper tolerances and tested correctly for proper function. The bolt for the optional safety lever is an M5 bolt and the spoon must be tapped with an M5 tap.

The two halves should be glued securely in place before the hammer is installed, and the smoke exhaust port can be sealed by any reasonable means. The original is just a piece of tape.