A collection of archive ephemera relating to the design, manufacture and entry into service of the 'Rose' Turret as fitted to Avro Lancaster aircraft 1943-45 including A Pictorial Record of the Development and Production of the 'Rose Turret' Type 'R' No.2 Mk1 with .5in. Armament published by Rose Bros (Gainsborough) Ltd, original photos, drawings, text, perspex covers; reports, correspondence between the manufacturers and Air Vice Marshall E.A.B. Rice, patent specifications and letters, and other correspondence, one letter being signed by Air Chief Marshall Sir Arthur Harris and 'No.1 Group RAF Bomber Command Self-Help' Erection of R.B. Turrets Helmswell No.1 Group RAF being a 10-day work instruction with original photographs and typed text; and a cast, plated and mounted model of a Lancaster, the base engraved 'Bawtry 1943'. Wingspan -- 17¾in. (45 cm)