Trackless Sliding Door Kit: Our concealed sliding door hardware features aluminum alloy tracks and nylon silent rollers, enabling smooth and quiet Installation Notes:1. Door panel must exceed door opening height by 65-70mm (2.6-2.8 inches) 2. Door panel thickness must be between 40-50 mm (1.6-2 inches). 3. Track length = door panel width. 4. Includes complete hardware set, supporting wooden doors up to 176 lbs. Verify compatibility before purchase to ensure smooth with Soft-Close: Equipped with a buffer to minimize noise and wear while eliminating tripping or collision risks from external door closers. Applicable only to wooden door panels. Installation Grooves: Top door panel requires a 1-inch L-shaped groove; bottom track requires a U-shaped groove. installation instructions and precautions in the images first. After installation, open and close the door multiple times to verify proper of the door closer. Versatile Application: Overhead sliding door tracks suit living rooms, kitchens, bedrooms, bathrooms, laundry rooms, pantries, walk-in closets, studies, exam rooms, and more. Also compatible with pergola doors, barn doors, garage doors, and pocket doors.