Scubapro Twin Jet Fins Adjustable - Cobalt Durable Monprene construction will last a lifetime of active diving. Patented split fin propeller technology produces lots of propulsion with minimal effort. Drag-reducing vents where foot pocket and blade meet radically decrease drag on both up and down strokes. Foot pockets extended soleplate allows you to maximize the amount of energy you expend on each kick without wasting energy. Extra-wide foot pocket is ideal for drysuit or semi-dry suit boots as well as standard warm water boots. Quick-connect swivel buckles allow for easy donning and doffing. Spring heel straps are optional.