These 15 inch Stay Down Progressive Release Bases are designed to flex and absorb energy as a player slides into the base. In case of hard, uncontrolled slides the progressive release action allows the base to flex until enough force is applied to pop the base free from its mount unlike a stationary base

The Stay Down(R) Convertible base converts stationery bases to Progressive Release(TM) bases without replacing existing ground anchors. The Stay Down(R) Convertible tee fits both 1'' and 1 1/2'' sleeves. Ground anchors for new installations are sold separately.