comprehensive sliding wardrobe door hardware kit, designed to facilitate smooth, quiet operation for heavy cabinet doors.Hardware Component OverviewMain Adjustable Bottom Roller (Right): Features heavy-duty internal tension springs, dual vertical adjustment screws, and a smooth nylon convex wheel to take the load and adjust door height.Upper Guide Rollers / Runners (Left): Two multi-wheel top guide fixtures featuring white nylon wheels designed to secure into the upper track profile to keep the door properly aligned without wobbling.