The Index screw anchor THE is a fastener made of carbon steel of sizes 6, 8, 10, 12, 14, 16 and 18. The Index screw anchor TXE is a fastener made of stainless steel of sizes 6, 8, 10 and 12. The fastener is installed into a predrilled cylindrical hole. The special thread of the fastener cuts an internal thread into the concrete member while setting. The anchorage is characterised by mechanical interlock between fastener and concrete.