
Air Psychrometer Mark V, with aircraft wing strut mounting straps

Air Psychrometer Mark V, Air Ministry Ref No.6A/424. By Simmonds & Webster, London, serial no. 299/400 [1940]. With straps for mounting on aircraft wing strut
Air Psychrometer Mark V, Air Ministry Ref No.6A/424. By Simmonds & Webster, London, serial no. 299/400 [1940]. With straps for mounting on aircraft wing strut