Optimum Double Sided Rotary Adapter is designed to work with Optimum Double Sided Wool& Double Sided Foam Pads. With the Optimum Double Sided Rotary Adapter you can easily switch between wool and foam pads. Additional benefits include a more balanced pad since the pad is always centered. The Optimum Double-Sided Rotary Adapter has a 5/8 -11 internal thread which screws onto a rotary polisher. On the other end of the adapter is a short 5/8-11 external thread that attaches to a Double-Sided Pad.