Next let's look for the backbone of this Backbone. It's in this area here, near the word "Backbone."

The sliding clamp mechanism uses a pair of flat spiral springs that unroll when you pull the handles apart. This provides more consistent compression and a tighter grip than the Razer Kishi, which uses helical extension springs to embrace your smartphone.

Flat springs (AKA constant-force springs) can also be found in seatbelts and tape measures.