One part is listed as suiting Shed Man™ sliding shed doors: a shed door carriage and roller, also listed as replacing Treco™ and Victa™ rollers. A single-part range is a narrow answer but a clear one — on a sliding shed door the carriage and its wheel take all the wear, running in an exposed top track that collects grit and rust, while the door sheet outlasts them several times over. Because there is only the one option, fitment is the whole question. Take the old carriage off the door and compare it to the product photographs, then measure the roller diameter and the spacing of the fixing holes. If the original mounts a different way, or the wheel sits on a different axle position, this is not the replacement for it.