Mills bomb, infantry weapon.
In 1915 a grenade devoloped by William Mills, a Birmingham engineer, began to be used by British troops. the bomb had a central spring-loaded firing-pin and spring-loaded lever locked by a pin. Once the Mills bomb was in the air, the lever flew up and released the striker, which ignited a four-second time fuse, allowing the thrower time to take cover before it exploded. When the grenade went off the cast-iron casing shatterd producing a shower of metal fragments. The grenade weighed 1 1/2lb in weight and would normally be carried on a truck. when on a man number would depend on circumstances. One could be carried on top of a full bandoleer in the mk2 ammo pouches.
These range in price from about £35.00 upwards. There are replicas and de-activated available but there is no need for you to buy any unless you feel like adding a few to your own collection or for helping with displays. They are not a necessary purchase.