Gear loops Harnesses vary in the placement and number of gear loops they offer. Choose a model with enough gear loops to comfortably accomodate your rack, but not so many that they become cumbersome. While this is handy for carrying lots of gear on an aid climb, it can obstruct a quick grab for gear on a difficult free climb. But if you like to keep your gear on your waist, you'll want four. I prefer to have extra loops because even if I'm not using them for carrying gear, I can tie a light jacket through one of the rear loops or clip a water bottle there.
Loops vary in size and location on the waistbelt.
So, regardless of their number, check to see that the loops put the gear where you want it. The front loops should be placed far enough back so that your gear doesn't fall into your lap when you high step. The back loops should be accessible enough for you to see all your gear and make a desperate grab for that large cam you stashed for a steep offwidth. The loops shouldn't sag too far below the waist belt either, or your gear will start swinging into the backs of your knees. Nor should they be so large that you hold 15 carabiners per loop, making it impossible to grab the biners that become wedged in the middle of the pile.