Self tightening car stop, CS-2. Car stop is assembled on head of rail by tightening 5 bolts, and driving the wedge from the rear. Tighten bolts periodically and re-hammer wedge if loosened. Stop stands 15-inches above rail. Weight: 107 pounds. For exposed rail track. Car stops are for flat track only. Car stops must be used in pairs. Use bumping post inside building. Product of Aldon ® Company.