Length - 24", Width - 9".

I think these are scuba diving fins. They are a lot bigger than the fins I have used for swimming.

There is an "M" on the bottom, I think this means a Medium size. They fit me about right with out boots, my heal is at the back of the bottom, have lots of strap left to make bigger. I'm a men's 9.5. Most sites say to wear with boots, so if I had boots on my heal would hang over the back a little.

Found this size chart on a web site:

Fin size MD/LG

US Men's shoe size 6.5-7.5

US Women's shoe size 7.5-8.5

There is a small split on the top of one (within the "Mares" label). See the photo, may have to view it on my web page to see the split. Otherwise in good condition.