Sold in 12 inch (30.5cm) lengths. Line the inside of your hat with a strip of this dark grey 1/4 inch (6mm) thick self-adhesive foam to get a tighter fit. White peel-off backing reveals adhesive side. One length of foam can shrink inner hat circumference up to about 3/4 inch (approx. 2cm). Cut it shorter if you only need a slight adjustment, or order two lengths to fully line the inside of your hat (would then decrease circumference by a full inch). Removable, should not damage your hat. Neoprene sponge rubber, made in Canada.
Dimensions: 1/4"x 3/4"x 12" (.6x1.8x30.5cm)