7-PrG
this was Merr-Sonn's proton grenade, produced during the height of the Galactic Civil War. The 7-PrG had a magnetic base, which allowed it to be placed in virtually any position. They were timed devices which were armed by twisting the base, and activated by depressing a plunger at the top. The Alliance used these grenades in the destruction of the shield bunker on the Forest Moon of Endor, during the Battle of Endor.