diameter 40cm [magnetic opening and closing]] diameter 45cm [magnetic opening and closing]] diameter 50cm [magnetic opening and closing]] diameter 55cm [magnetic opening and closing]] diameter 60cm [magnetic opening and closing]] diameter 65cm [magnetic opening and closing]] diameter 70cm [magnetic opening and closing]] 80cm diameter [magnetic opening and closing]] 80cm diameter widened [inlet depth 59cm]]

one-layer model [folding design/with pulley]] two-layer model [folding design/with pulley]] three-layer model [folding design/with pulley]] four-layer model [folding design/with pulley]] five-layer model [folding design/with pulley]]