Simple, sturdy, fix cheeked pulley for hauling, simple tyroleans, and self rescue.
Carry one of these and two oval krabs with your basic SRT rig, and it is possible to create an effective pulley jammer system (as long as you know how to make it in the first place).
Simple bearing, so not as low friction as bigger models. However, it is small enough to carry unnoticed, until it is needed. Also works in conjunction with a Mini - or Pro traxion to make a very effective 2:1 hauling system.
Note that the Fixe works best with the CT Simple+ hand ascender and the Petzl Ascension. However, it can still function well as part of a 3:1 Z rig if a separate pulley-jammer or Traxion assembly is also available.
Requires an oval krab such as the Axxis for greatest effectiveness.