Field clinometer MK VI used in conjunction with the QF 25 PDR field gun. This device was mounted on a fitting at the breech end of the gun barrel and used to accurately indicate the elevation of the gun barrel. The device is calibrated in degrees and minutes and is adjustable enabling the weapon to be accurately aimed.ww2, 25 pdr, qf 25 pdr, 25 pounder, field gun, clinometer, field clinometer mkvi, field clinometer, clinometer mkvi