Lackmond 5" Turbo Cup Wheel SPPSTC5N18. SPP Series Segmented Turbo Cup Wheels are an excellent cost performance value. The segments are arranged diagonally around the rim of the cup wheel allowing more diamonds to contact the work surface than with any other style. Because of this configuration, the Segmented Turbo design also provides the most stable grinding platform of any cup wheel - preventing gouging and uneven grinds.