copper brush,wear-resistant,flexible,suitable for condenser tubes cleaning, diameter can be 1/4~1", with M6 brush handle ... Brush for Condenser/Chiller/Evaporator tubes cleaning useSpecifications:Available for tube sizes 1/4"-1" Cleaning Diameter(inch)(mm)0.256.40 ... bigger size can be OEM or Customized. Stainless Steel Tube Cleaning Brush