I am an authorized dealer of crocs. Crocs come in many color and sizes. There are two types of Crocs that have the holes in top of them. One is the Caymen which is a narrow version of the Beach and they are sized individually. All Crocs are sized to fit men and women. The Caymen crocs for example(M5 W7) wi11 have a M and a W on the back of them. That means a Man 5 and a Woman 7. The other type with holes is called the Beach Crocs. They come in XS, S, M, L. The Small for example will have W 5-7 M 4-6. Not all Crocs will have a smiling croc on each side of them on the black buttons. Some of ours only have the smiling croc on the outside. Also crocs are manufactured in Colorado, Mexico and Canada. I am sure with the demand for these crocs, there may be other manufacturers crop up. Crocs are constantly adding new styles of shoes. They now have flip flops, slides, lace ups and boots for kids. They have also came out with a diabetic shoe but after contacting crocs, these can only be purchased with a prescription. Coming in October will be a variety of Collegiate shoes. (Alabama Roll Tide will be out soon and I am so excited). Also coming soon will be a Disney croc. I am not sure when these are scheduled for production.
I hope this helps with any questions you may have!