(Pack of 6) E-Track Wood Beam Holder Socket Fittings for Load Bar, Shelves, Custom Cabinet (Pack of 6) Etrack Wood Holder will fit all standard E-track Will work with 2"x4" or 2"x6" Lumber Spring Loaded Latch for Safety and Easy Adjustment Side and Bottom Lumber Mounting Holes for a Secure Load Heavy Duty Construction with Zinc Plated for Weather Protection