First decide what kind of rock climbing you will be doing most before choosing any rock climbing equipment. Some climbers are boulderers, which means they do not climb high and do not need ropes or harnesses. Bouldering is done low to the ground, so the boulderer will need a crash pad, a foldable cushion on which the climber will land should he fall. Rock climbing equipment for top-roping, or securing an anchor at the top of a climb through which a rope is run, will require several carabiners, webbing, a dynamic rope, a good harness, and other common rock climbing equipment.
The best rock climbing equipment will be appropriately sized, will be easily functional, and will be well-fitting if it is worn on the body. It is important not to buy used rock climbing equipment if possible, since it is difficult to tell what kind of stresses the equipment has been through before you purchased it. Ropes especially should be bought new, as they have a limited lifetime and need to be retired from use after a significant amount of climbing has been done on them. be sure to choose the correct type of rope for the right purposes: climbing is done on a dynamic rope that stretches under weight, and rappelling is done on a static rope that does not stretch as much. Dynamic ropes can also be used to tie anchors.
Choosing a good harness is an important step when buying rock climbing equipment. Be sure to choose one that fits snugly but comfortably, and one that is appropriately padded for comfort. It helps to buy a harness with sufficient gear loops from which carabiners and other climbing equipment can be hung. Make sure the buckles of the harness are easy to use and easy to check for proper security. If you climb year round, be sure to choose a harness that is adjustable enough to cinch down over thin shorts as well as over thicker snow pants.
When choosing a chalk bag, be sure to choose one that is large enough for your hands to fit in comfortably. Buying a lined chalk bag will prevent excess chalk from falling out of the bag while in use, and a drawstring that closes the bag tightly will prevent chalk from spilling out when the bag is not in use. The materials used to make the bag should be durable and rip resistant, as the bag is likely to endure some heavy duty abrasion and impacts.