Power - Their size has been optimised for improved efficiency in rivers and large lakes. Easy dressing - Self-adjusting straps with ergonomic heel cover. Buoyancy - Limits the risk of losing a fin if one accidentally comes loose. Propulsion - These fins have been designed for use in a sitting position. User comfort - For use with boot foot waders or wading boots. Anatomic design - 2 attachment points allow fins to fit boots in UK sizes 6. 5 to 12. 5 (EU 40-48). TECHNICAL SPECIFICATIONS: Weight: 1485 g (weight of the pair).Dimensions: 59 x 21 x 10 CM (one fin).Floating material. REPLACEMENT PARTS: Self-adjusting straps with ergonomic heel cover: reference 8665562 ADJUSTABLE FIN STRAP BUNGEE (PAIR)