The purpose of this biner is to avoid cross-loading while belaying.
Pros:
-Easy to install on belay loop.
-Doesn't require opening the gate to open the belay-loop lock (like the BD one does).
-Has a thick spine and large locking barrel to prevent a gri-gri from sliding in either direction.
-The locking barrel is damped, and so doesn't move if rattled while not locked all the way.
- The locking barrel has a lot of extra travel - even if it started to come open, it would have to twist many times before allowing the gate to open.
- Belay-loop lock spring tension is nice and high.
- Quite light for the functionality!
Cons:
-The belay-loop gate makes racking a gri-gri on your harness slightly more awkward. (The grigri ends up sitting at the large end, and the wire gate sits on your gear loop).
- The wide spine (a feature noted above) reduces the versatility of the biner, since it doesn't fit into small holes (bolts, etc) as easily. But that's alright, since it's meant just for belaying anyway.
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