From Remo:
The Modular Practice Pad™ Set is a 5-piece set including 6-3/4″ and 10″ diameter tunable Practice Pad™s with Ebony® and Ambassador® Coated drumheads for a real drum feel. Ideal for practicing in situations where volume is not permissible. Lightweight and portable, the pads are mounted on a strong, fully adjustable tubular frame.