They are held in front of the animal and function as sense organs similar to the antennae of other arthropods. Each has an eversible adhesive disk at its blunt tip. The disks are not apparent unless they are everted. The remaining four pairs of appendages are legs composed of six articles each. The articles are, in order from proximal to distal, the coxa, trochanter, femur, patella, tibia, and tarsus.
Most legs bear a claw or claws at the end of the tarsus.
The first pair is much smaller and more slender than the others and is used as a second pair of antennae. It is sensory. Species of the Ammotrechidae do not have claws on this leg but the eremobatids do. This leg is not used for locomotion. The remaining legs get progressively larger posteriorly and are used for locomotion.