Sleeve type anchors feature a split expansion sleeve over a threaded stud bolt body and integral expander, nut and washer. Anchors are made of Plated Carbon Steel, or Type 18-8 Stainless Steel. The Sleeve Anchors design allows them to anchor into concrete, brick and block. Sleeve anchors work by inserting them into a hole drilled into concrete. Turning the nut pulls the working end of the sleeve anchor up through the sleeve, expanding and anchoring itself securely in the concrete, brick or block.