Pictured here is a Boxwood 4/4 Guarneri chinrest with our matching Boxwood Guarneri GelRest. Also available in 1/2 size. The 4/4 size measures 65mm wide by 105mm long. It will also fit Dresden Large, Morawetz, Priska, Varga, and Wendling chinrests. The 1/2 size GelRest measures 55mm wide by 85mm long. The 1/2 size fits many smaller chinrests, like the Dresden.