The Dif-Fly is one of the older Dif-e-Yo yo-yo models, so you might say it's withstood the test of time. This yo-yo is a polished aluminum concave-shaped yo-yo. It weighs 56 grams by itself or 64 grams with the weight rings. It features Dif-e-Yo's KonKave bearing and friction sticker response system. The "F" series means that it features the new flush-mounted Dif-Pads, allowing for even better spin times and responsiveness.