Mungo MNA-S Hammer Screw Drive Anchors feature a plug with countersunk collar. This plug is made of premium-grade polyamide PA6 and has a long expansion zone for optimum stability. The screw component of this anchor features a reinforced screw head and buttress threading which allows for adjustment and dismantling. The MNA-S hammer screw drive anchor is suitable for use with concrete, brick, and stone.