If you want art to stay on the wall, use D-rings (avoid sawtooth hangers). I make frames and re-frame art, so I see and use a lot of hangers. (Last month I also saw what stayed on the wall during a strong earthquake, and what didn't.) These are well made and comparable to what you'll find in national art supply and hardware stores, but for a fraction of their price. If you've got a single frame to hang, then you won't need to buy a pack of 100, but this will save you money if you are hanging more than a few frames. This size is good for thin frames up to perhaps 16x20 inches, or for thicker wood frames up to about 11x14 inches with 30-lb test wire. If you've got a large, thick, or heavy frame or a mirror, go with the larger size D-rings that have two screw holes, use longer screws and heavier weight wire.