This plate was typically attached to the breech of the barrel housing and would house the spirit level. The spirit level was used in the sighting of the gun. The bronze plate measures 3 5/8 in. in diameter and the entire plate is engraved. There is an oval hole in the center of the plate where the spirit level would rest with two holes above and below. On either side of the oval hole are flourished engravings and in block letters engraved "Gatling Gun/Patented". At the top and bottom of the hole are larger screw holes on the outer edge.

Excellent overall with a warm aged brass patina and clear markings.