This is a multi-functional sock-type model that combines antibacterial, heat-retaining, and anti-slip functions. When used in conjunction with full-foot fins such as Mews and Super Mews, it is much more comfortable than using fins with bare feet. The size is only 29cm, but the regular price of ¥9460 is now on sale for a great price of ¥4320. Shipping is also included, making it a very good deal. The product is brand new and unused, so you can use it with confidence upon arrival. Thank you for your consideration.