Repair those unpleasant holes and cracks to make your home and surroundings look beautiful with Polycell Polyfilla stronghold. Polycell Strong Hold Polyfilla is the quick way to rock-solid anchoring of stair handrails, fencing, curtain rails, switchboard cabinets, socket outlets, loose bricks, rainwater pipes. It sets rock hard in 15 minutes (depending on conditions) and gives a perfect white finish. Perfect for repairing concrete and cement floors, tile joints, brickwork, paving and glass block joints. Suitable for any size, depth of repair, you can use this indoors and outdoors.