Q-Snap frames are made from PVC tubing, making them lighter and more durable than other materials. The clamp design for holding the fabric is gentle and simple to use - just lay the fabric over the frame, then gently push the clamps down, stretching the material around the outside of the frame. The ribbed inner surface of the Q-snap clamps hold the tension for your preferred adjustment. Simply turn the clamp outward to tighten, or inward to loosen. Measures 6" x 6".