What is the difference between neoprene and sponge can huggers?

When it comes to drink huggers we offer 2 materials. The sponge material is the most economical of the 2 choices and is made of a foam rubber backing with a polyester outer covering. The neoprene material is the same material a wetsuit is made from and it is more durable, flexible and better insulating than the sponge material but they are also more expensive. The easiest way to tell the difference between the two is the stitching. On the sponge material they are sewn with a straight stitch on the inside of the material where the stitching isn't shown. On the neoprene material they are sewn with a thread color to compliment the hugger in a zigzag stitch on the outside that is visible.