This is a Johnson Hardware 1060 Soft Close Hanger, designed to prevent pocket doors from slamming.The kits include a soft-close mechanism, hangers, and necessary hardware for installation.It is compatible with Johnson 100 Series tracks and can support door weights up to 200 pounds
If you purchase them retail, they are approx. $30 each. I'm offering them at $15 each or $75 for all 6.