I love these Mantra soft blades and S-wing foot pockets. No cramps in the calves!

But I bought these based on the shoe size chart on the website. They arrived too big. So I thought, I'll keep these foot pockets for possible cold water diving. I can wear a sock. Freedivershop would have exchanged them out for no cost, except freight, which is significant between the US and Italy. I bought the next smaller size foot pocket, expecting that changing blades to foot pockets would be simple.

For some reason, the blades are GLUED in to the foot pocket by the manufacturer! (This is great if you never need to change out the blade/foot pocket.)

In answer to that, the FreediverShop sent me a link to a video that shows me how to install new blades into new foot pockets. Not helpful for removing. I requested assistance again and I was told that Cetma would have a technician prepare a video demo in a few days. A week later it did not arrive.

In the meantime, because I need to break them in before a trip in a few weeks, I removed them myself without guidance from the manufacturer. I used a utility knife, single edge razor and acetone. It takes about 1.5 hours per fin. Insertion of the blade to the new pocket was easy. I used a small amount of silicone sealant on the sides where the pocket meets the rails. The end result was that the original foot pocket is probably still usable, but there's some missing rubber on the inside.

In summary, I love the fins! In my case, at least, ordering a smaller size than my shoe size would have worked. At some time in the future if the foot pocket wore out, it would be simple to remove it, if destroying it would be OK.

Question to Cetma; Why do you glue them with permanent glue when the two screw installation would work fine? The benefit would be that a mildly handy customer could change them out without destroying the pocket.