There are three sizes of headband, because good things come in threes. The parts can be identified by the mark on the top of the band. For example, the SMALL size of headband has a small triangular mark.

The sizes are relative, and don't correspond to any particular size of head. You might want a small size headband if you have a "small" head, or if you have a "large" head but want a higher clamping force.

For instructions on how to use these headbands, consult the assembly wiki (specifically, Part 4): https://github.com/ploopyco/headphones/wiki/Part-4%3A-Headband

We're always looking for feedback, particularly on ergonomics. If you try all three of these designs and find none of them fit you, please email us at contact@ploopy.co There's a decent chance we can create another size that'll work for you.