AK Pro Training Fins Size Guide

The AK Pro Training Fins are open-design training fins engineered to enhance kicking technique and build leg and core strength. The open fin design allows better water flow through the blade, promoting natural foot movement and reducing ankle strain during long training sessions. By improving body alignment and developing a more powerful, efficient kick, the AK Pro fins are well suited to technique-focused sets and endurance conditioning work.

Available in five sizes covering EU 36–45. Sizing is based on EU shoe size, with UK equivalents and foot cavity measurements also shown.

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How to Size : AK Pro Training Fins
AK Pro Training Fins foot cavity and foot length measurement guide

Use your EU or UK shoe size to find your size. The foot cavity measurement is the internal length of the fin’s foot pocket and is provided as a secondary check for those between sizes.

  1. 1
    Match your usual EU or UK shoe size to the size table below. EU size is the primary reference; UK equivalents are shown alongside.
  2. 2
    The foot cavity is the internal length of the fin’s foot pocket. If between shoe sizes, compare your foot length to the foot cavity to confirm the better fit.
  3. 3
    If your measurement falls between two sizes, size up for a more comfortable fit. The open fin design means a slightly larger size will still perform well without compromising the training benefit.
Sizing Table : AK Pro Training Fins
EU Size UK Size Foot Cavity (cm)
36–37 3.5–4.5 22 cm
38–39 5–6 22.5 cm
40–41 6.5–7.5 24 cm
42–43 8–9 25 cm
44–45 9.5–10.5 26.5 cm

EU shoe size is the primary reference. Foot cavity is the internal length of the fin’s foot pocket. If between sizes, size up.

Fit Notes : AK Pro Training Fins
  • Size using your EU shoe size as the primary reference, with UK equivalents shown alongside. If your shoe size falls between two ranges, use the foot cavity measurement to confirm the better fit, or size up for comfort.
  • The open fin design allows water to flow through the blade during each kick, reducing ankle strain and promoting a more natural foot movement that closely mirrors an unassisted flutter kick.
  • The fin should fit snugly around the foot with the foot seated fully into the foot pocket. If the heel is lifting during kicking, try the next size down.
  • AK Pro fins are ideal for long training sessions : introduce them gradually if you are new to fin training, starting with shorter sets and building volume as your legs and ankles adapt.
  • Rinse in fresh water after every session and allow to dry naturally away from direct sunlight and sharp objects.
  • Unsure? Contact our team or call +44 1827 330600.
Frequently Asked Questions : AK Pro Training Fins

Match your EU or UK shoe size to the size table above. EU size is the primary reference. If your shoe size falls between two ranges, compare your foot length to the foot cavity measurement to find the closer fit. If still between sizes, size up.

The foot cavity is the internal length of the fin’s foot pocket in centimetres. Measure your foot length from heel to toe and compare it to the foot cavity column. Your foot length should be equal to or slightly shorter than the foot cavity for a snug but comfortable fit.

Open fins allow water to pass through the blade during each kick rather than directing all resistance through the foot pocket. This reduces load on the ankle, promotes a more natural foot movement, and makes the fins better suited to long training sessions compared to fully closed blade designs.

The AK Pro Training Fins are designed primarily for freestyle and backstroke kick training where a flutter kick is used. They are effective for kick drills, body position sets, and general conditioning work in the pool.

Size up. A fin that is too small will restrict ankle movement and be uncomfortable during training. The open fin design means a slightly larger size will still perform well and deliver the training benefit without causing discomfort on longer sets.

By providing propulsion through each kick, the fins allow swimmers to maintain a higher, more horizontal body position in the water. This gives the swimmer the opportunity to feel and practise correct body position during kick sets, which can improve overall stroke efficiency over time.

Yes. The AK Pro fins are suitable for swimmers at all levels. If you are new to training with fins, introduce them gradually : start with shorter sets and build volume as your legs and ankles adapt to the additional resistance.

Rinse in cold fresh water after every session to remove chlorine and debris. Allow to dry naturally away from direct sunlight. Store flat away from sharp objects to maintain the fin’s shape over time.