Durable aluminum rail and cast-aluminum pedals stand up to indoor and outdoor use Used to brace a runner's feet before the start of a sprint race, allowing sprinters to push off the block without slipping 4-angle pedals can be adjusted to the runner's preferred push-off angle Pedals move up and down the number-marked rail for runners to find the proper foot distance Includes spikes and a spike wrench to secure the block in place on nearly all racing surfaces