Lightweight aluminum belay device, perfect for climbing. The Petzl Reverso 4 is a belay device that combines safety and ease of use. - Brand: Petzl - Model Name: Reverso 4 - Material: Aluminum - Application: Climbing Thank you for viewing. Purchased new about 7 years ago. I don't climb, but I bought it to carry in case of emergencies during mountain climbing. I practiced with a rope, but I never actually had the opportunity to use it. I am selling it because I no longer need it. There are some scratches and dirt. This is a used item.