Confast’s hammer drive anchors are designed for permanently attaching junction boxes to solid concrete. When the anchor has expanded, the junction box cannot be removed without possibly damaging the junction box or cutting the head off the anchor. It is available in 3 / 16 - and 1 / 4 -in. diameters.
Confast’s double expansion anchor is designed for anchoring into concrete, brick or block base material, especially for projects where the base material is soft. It is made from a rust-resistant die-cast alloy and has two expansion cones. Two spring steel bands wrap the two halves together and allow the anchor to expand against the concrete at two points.