This complete luggage wheel replacement kit includes four 50mm wheels designed to extend the life of your suitcase. The kit comes with everything needed for installation: four axles in two sizes (34mm and 37mm), eight 12mm washers, four 16mm screws, eight 8mm spacers, two wrenches, and a 6mm by 93mm drill bit for removing old wheels. The wheels feature precision groove ball bearings that turn smoothly without needing gap release when tightened. A plastic bush prevents locking during installation. These wheels passed a 32km treadmill test carrying 22kg at 4km per hour with no loosening or falling off. Designed for most modern 4-wheel suitcases with single wheel construction where the axis is held by suspension on both sides with the wheel positioned in the center.