Each 2-pack contains 2 Xact-Fit rings in size 19. The incredibly popular PlayZone has proven that our revolutionary incremental Xact-Fit 2.5 mm (0.1 mm) cock ring sizing system is the most precise on the market. While the Xact-Fit rings feel super strong, they are soft enough to be put on and taken off easily. They offer a very comfortable and effective fit. The size refers to the ID in inches (10 = 1.0 ID, 11 = 1.1 ID, etc.). All 14 Xact-Fit ring sizes are now available in single size 2-packs. 3-ring sets of M, L, XL, and Mixed are also available. Not sure of your size? We recommend starting with the Play Zone Kit, which includes 9 incrementally sized Xact-Fit rings on a bright orange mini traffic cone. Each Xact-Fit ring is labeled with its size, so you won't have to guess anymore! Stack the rings for added fun.