These tubular tyres are designed for tubular rims, these are glued on using tubular cement or tubular tape. They are the preferred choice for serious riders and professionals when all that matters is performance. A tubular is a sealed unit with an inner tube sewn into the tyres casing, this means the tubular is perfectly round in profile and offers a better feel when cornering. Vittoria have introduced open tubulars which are the same design as their tubular tyres but with a bead for use on a clincher rim, these will offer the closest feel of a tubular but the ease of repair associated with a clincher. Sizing is subtly different to clincher wheels and can be a bit confusing as most manufacturers still quote the old imperial sizes. However there are only 2 real sizes: 26" is the same as 650c, then 27", 28" and 700c are all the same size.