Wintec™ window catches are replaced here by two parts, a keyed window catch and spring and a non-keyed version, alongside a single 25kg adjustable patio door carriage and roller that covers the sliding door rollers. Two of the three products being catch-and-spring sets points straight at the failure: the spring behind the catch loses tension or snaps, the catch stops holding the sash shut, and the catch body is usually replaced with it rather than the spring alone. Before ordering, check whether the original is keyed or non-keyed, because the two are not the same part, and compare the fixing hole positions on the sash. For the carriage, the 25kg rating is the number that matters — check the weight of the sliding panel. The same carriage also replaces Boral® and Dowell® Mk5C rollers, and A&L® rollers.