Clarke Pistol Grip Needle Scaler & Hammer Kit Model Number: CAT84 This is the Clarke CAT84 2-in-1 pistol grip needle scaler and hammer tool, it can also be called a needlegun scaler or needle gun. Compare View Product Clarke Air Needle Scaler Model Number: CAT51 In-use data available The Clarke CAT51 Air Needle Scaler (or Needlegun scaler or needle gun) is suitable for fast and effective rust and scale removal. Compare View Product