Simpson 1/4" x 3" Zinc Nailon Pin-Drive Anchor ZN25300B Pk of 1000Zinc Nailon anchors are low cost, mushroom head anchors for applications under static loads. The anchors are easily installed by hitting a hammer on the head that drives the pin through the anchor, expanding the body of the anchor to hold it in place. Ideal for use in concrete, CMU, brick, and other base materials. Pin and head configuration is designed to make anchor tamper resistant. This product is not for use in overhead applications. Model No.