I’ve settled on what items I always keep on my climbing harness (BD Momentum).
- BD ATC Guide with pear carabiner. Common belay/rappel device with an autoblocking mode. Autoblocking mode is good for bringing up a follower at an anchor, since the autoblock works as a “progress capture” device that will hold the rope if you were to accidentally let go. It’s super easy to setup and requires one additional locking carabiner.
- Metolius Alpine PAS, with locking carabiner. A personal anchor system is just a chain of strength-rated loops that you use to clip into an anchor. The individual loops make it easy to adjust the distance from the anchor, and provide some redundancy since you can clip into multiple loops. The Alpine PAS is a lighter version of the PAS. One thing to note, this can’t take factor 1 falls so you should tighten it up so that it is always loaded (Petzl Connect Adjust can take dynamic loads though).
- 13.5 inch HollowBlock, with locking carabiner. Used as a rappel backup mostly. Why not a loop of cordelette? Mostly preference. The HollowBlock is a fixed loop with the ends stitched together as a bar tack. It’s made of this hollow sheath cord that grips extremely well as a klemheist or prusik, requiring usually just two wraps to hold. The absence of knots in the loop makes it slightly less fussy. I believe it’s lighter than most cordelettes. Downsides might be that you can’t untie it and use it for something else like anchor building, and that its rated strength is not as high as cordelettes I’ve seen.
- Extra locking carabiner. Good to have for putting the ATC Guide in autoblocking mode.
- Emergency locking carabiner.