The small style (1 quart capacity) is 8" in diameter and has a lip hook to secure it on a pot edge. It collapses to 1" thick. The large style (2 quart capacity) is 10-1/4" in diameter and has a fold-out stand for in-sink use. It collapses to 1-5/8" thick. Both styles have sturdy plastic frames with flexible silicone strainers and silicone-coated handles.
Heat resistant to 250°F/120°C and dishwasher safe, they are a boon for any space-constrained kitchen.