Italian Red/White/Green roundels. These were introduced in 1944 on Italian aircraft flying on the allied side, and were retained post-war by the Italian air force. From 1989 they began to be replaced by a modified version with the white ring reduced to a very thin circle, but this type could still be seen on some aircraft well after that date.
These decals are scaled to represent 30", 36" and 48" diameter roundels in 1/300 scale. The actual diameters are approximately 2.5mm, 3mm and 4mm.