The Surly Lou tire is the 26 x 4.8" rear-specific mate to Bud. Lou's tread is much like Bud's with tall knobs designed to grind crawl and claw its way over rooty rocky wet muddy loose or otherwise inhospitable terrain. Lou's tread pattern is a bit different however made for stability while both braking and accelerating. Its casing is durable thin-walled 120tpi which conforms well to the ground surface shape. Folding Kevlar bead.