Part of the tibia of a grasshoppers jumping leg

Tibia-piece at 15,5x magnification.

 

I suppose the fine hairs are sensors and used to identify the surface, while the barbs (or spines), which point backward, are used to hold onto surfaces. Due to the large muscle in the hind leg, the insect works the spines to take hold of the surface so it may leap into the air and fly.

Done