This rotating tool fits the solid the fuel Aga range cooker barrel only. It locates into 2 opposite pre drilled holes in the hob (you will have 4) and allows the barrel to be rotated to rub off soot build up. Frequently known as a cow horn tool due to its shape! This should be used MONTHLY on the solid fuel Aga range cooker. Dimensions 15 inch long x 8 inch high. Telescopic centre section to align prongs with holes exactly. This means the tool will fit all barrels as over the years there have been small variations.