An auto-lock descender which has gained popularity, particularly with professional users and some rescuers. Apart from abseiling it is also rated for hauling and lowering loads up to 200kg, and lifelining. It is described as being compatible with ropes from 10mm to 11.5mm; although light and experienced users have certainly used the Rig on ropes that are considerably thinner than this - NB that the load before slippage on the 9mm Petzl Push rope is 3.3kN
For thinner ropes additional braking is recommended, beyond the use of the stainless steel insert on the body of the Rig. Petzl recommend the Freino, what is *not* recommended would appear to be large aperture (oval) karabiners.
Note for expedition cavers, no parts of the Rig are changeable if they wear out! Although they seems to be durable on dirty ropes, this should be a consideration, at least if one is taking a well-worn Rig into a remote caving area.