The following rope grabs are all variations of the same basic design:
Image | Rope Grab | Manufactured | Side Plates | Lever Locking Tab |
---|---|---|---|---|
|
ISC Rocker | 2006 (?) | 3.9 mm. Anodized Aluminum | Yes |
|
NTR Rocker | 2017 (?) | 3.9 mm. Anodized Aluminum | Yes with forward fold |
|
Proverti AC080 | 4/2015 | 4.4 mm. Anodized Aluminum | Yes |
|
Proverti AC081 | 4/2015 | 2.5 mm Stainless Steel | Yes |
|
SAR Rocker | 2012 | 3.9 mm. Anodized Aluminum | Yes |
|
Singing Rock Locker | 1/2008 | 4.0 mm. Anodized Aluminum | Yes |
|
Troll Rocker, Version A | ~2001 | 4.3 mm. Anodized Aluminum | No |
|
Troll Rocker, Version B | ~2003 | 3.9 mm. Anodized Aluminum | Yes |
|
Vento (Венто) Rocker | ~2019 | 3.9 mm. Anodized Aluminum | Yes |
|
Xinda Rocker | ~2014 | 4.0 mm. Anodized Aluminum | Yes |
|
Vertical (Вертикаль) Rocker ver 0115 |
12/2021 | 4.0 mm. Anodized Aluminum | Yes with forward fold |
|
Yates Rocker | ~2003 | 4.3 mm. Anodized Aluminum | Yes |
|
Z&W Rocker | ~2019 | 4.0 mm. Anodized Aluminum | Yes with forward fold |
Each of these is a compact, lightweight (except for the stainless steel Proverti AC081) fall arrest that can also be used as a ratchet when hauling loads over a pulley. They can all be used as rocker-arm ascenders, but that was not the original design intent for the Troll Rocker, the progenitor of the others in the chart.
These have no sharp teeth to cut the rope sheath. Some informal testing suggests that, lacking teeth, these can slide before engaging, but normally the slippage is less than a foot. The cases where I observed this were somewhat contrived (i.e., I held the grab in a specific position and carefully dropped the load straight down), and so I'm not too worried about the slippage. I would be far more concerned if they had sharp teeth and didn't slip at all.
The top hole is used for releasing or offloading a locked rocker by placing a carabiner in the hole and pulling toward the slack rope.
Except for the early Troll, each of these incorporates a lever lock. Troll added one to theirs before the others came out. The lever lock works, but one needs to be careful not to bump it so that it accidentally disengages. A carabiner in the upper hole can help prevent this. When the lever lock is disengaged, it blocks access to the upper hole.
The NTR, Vertical, and Z&W have a forward 90° bend at the top of their lever lock, making their locks much easier to operate than the others that rely on shallow rounded serrations.
Troll warns that using a rocker as a on soft
or loose-sheathed ropes can cause the rope sheath to slip or tear. They also warn that rope conditions (water, ice, mud, dirt, etc) as well as rope diameter, manufacturer, etc. will affect device performance. These warning apply to all of these fall arrests.