Vertical ski carry attaches your skis straight up and down on one side or the center of the pack, rather than angled or spread across both sides. It's a simpler, more minimal system you'll mostly find on ultralight touring packs.
The big advantage is speed—sliding skis into a vertical sleeve or strap is about as quick as it gets. It also keeps your skis close to your body with less protrusion, which means fewer snags on branches in tight trees. The trade-off is balance: carrying skis on just one side can feel lopsided, especially on longer approaches or technical terrain.
Vertical carry is worth considering if you're an ultralight-minded skier doing shorter bootpacks or if you frequently ski tight glades where a wider A-frame setup catches on everything. For longer tours or heavier loads, A-frame remains the more stable and comfortable choice.