Gun Sight, Reflector, Mk IIIA 7A/1313 RAF A-20 and includes descriptions

and includes descriptions

This is an authentic WWII-era Bomb Station Distributor Selector SD-1 as used in the US Navy's TBM Avenger multi-purpose carrier-based bomber

Pulling and turning would adjust the Nose Down marker

We have not found documentation of its use

primarily trainers

Gun Sight, Reflector, Mk IIIA 7A/1313 RAF A-20 and includes descriptionsHere is a WWII era Reflector Gun Sight Mk IIIA, 7A 1313. The Mk IIIA was adopted by the RAF as the standard turret and free gun sight for their aircraft. The Mk IIIA consisted of a detachable lamp unit and an upright sight head. The lamp unit is removed by depressing a small button on the bottom of the housing, revealing the bulb and circuitry (this example is quite tight). The brightness of the bulb was adjusted by the gunner by rotating the rheostat