The Van Buren Urethral Sound / Dilating Bougie (10 Char, 27 cm / 10 ¾ inches) is a slim, single-ended urological instrument used to dilate early-stage urethral strictures, clear obstructions, and navigate the male urethral pathway.

The sizing term "Char" stands for Charrière, which is mathematically identical to the French gauge (Fr) system.