Hello, I wanted a reducer for my Ryobi Circ/saw as the new blades were a 20mm hole unlike the saw which is a 10mm bore, As seen in other posts the rings are cheap but some guys want £7+ postage. So I got the vernier out and measure some washer. RESULT I have a "Blue Spot" kit/box of washers and the largest being 20mm out and 10mm in, job done. a dead fit. So think on new saw blade! old washer box. Livestrong Kenny
