Replacement hardware to suit G.James® windows and doors — adjustable sliding door carriages and rollers in acetal and stainless steel, sliding window carriages, and screen door guides. G.James® is a heavier commercial-leaning system, so the stainless options matter here more than on residential frames, particularly within about a kilometre of the coast. Carriages are listed by overall length and by load rating; measure the old one end to end and check the rating against the door weight rather than matching on size alone.