For 65 and 90 mm (2 1/2" and 3 1/2") or deeper hollow walls with finished wall surfaces 6 to 38 mm (1/4" to 1 1/2") thick. Corrosion resistant stainless steel. One required for each flange. Fastener will support 136 kg (300 lbs) load. WingItTM is a trademark of WingIt innovations, LLC.