Even with an arm type, it can be installed thinner. Extends the arm to create a free-flowing look, and folding the arm for compact storage. Arm type allows you to pull the TV out of the wall for use. The aluminum alloy has a strong construction, so you can pull it out to the longest possible length for a peace of mind. The arm type is usually thick due to the arm type, but this type is 1.4 inches (3.5 cm) that can be thinned to the extremes.