The most popular kind of plyometric boxes for CrossFit gyms are the wooden 3-in-1 and stackable plyo boxes. The 3-in-1 boxes are what most gyms use because they are versatile and stable. A 3-in-1 plyo box will be 20-24-30″ and allows all of the prescribed heights, as well as the extra high heights for advanced athletes.
Another type of wood plyo box is the stackable plyo box. Stackables allow you to start low, and go as high as you need to. The low starting height is great for beginners, children, and the elderly. Many smaller women or children have a hard time jumping 20″ when they first start, or they might be scared to jump that high. The stackables allow you to start as low as 8″, and they are lightweight enough to be able to be moved by anyone. Additionally, you can go beyond 30″ with these as long as they are wide enough to be stable at that height.
The advantages of wooden plyo boxes versus metal plyo boxes are that the wooden ones are easier on your shins if you miss a jump. Metal ones will dig into your shins and cause cuts, while wooden ones almost always have sanded edges that allow the athlete’s foot to slide down the side of the box rather than miss it and bang their shin into the upper edge of the box.
Another advantage is that the 3-in-1 boxes have 3 different heights, while the standard metal boxes would require you to have 3 separate boxes to support that many variations. This leaves a gym owner in a situation where they have to guess how many of each size they need and makes it difficult when class demographics don’t match the equipment.