Our monofin blade stiffness is based on 3 stiffness flexes (Soft, Medium, and Hard) and two blade sizes (1 and 2). Size 1 blades are slightly narrower, shorter and softer than size 2 blades although the difference is quite small (2 centimeters of length and width). As an example, a Blade Stiffness Soft 1 is a Soft flex blade of size 1 and is slightly narrower, shorter and softer than a Blade Stiffness Soft 2.
Both blade sizes 1 and 2 are appropriate for men and women. If you are on the smaller and lighter side or prefer a more agile monofin, a size 1 blade is for you. On the other hand if you are on the taller or heavier side or prefer a more powerful monofin, go with a size 2 blade.