Unlike most of my decals, this set (along with 600-GB-2, 3 and 4) is specifically scaled, rather than supplied in "generic" sizes. (Ie. my usual 24", 30", 36" and 48" scale diameters.)
Instead, these decals scale out to the regulation sizes for fighter aircraft when used on 1/600 scale models. I will also be producing "generic" sheets of RAF decals in due course, to suit other aircraft types.
Note for customers looking to do Battle Of Britain aircraft; I'd recommend skipping this sheet entirely, and getting one each of 600-GB-2, and 600-GB-3. The latter sheet (Type B roundels) has roundels of this type for underneath the wings, as the Type B was very rarely used in that position.