DIY Battle Ropes- Good for Crossfit and bootcamp type workouts. Just go to your local fire dept. and get an out of service fire hose for FREE. Take whatever you can get but a 2.5 inch hose is good size (go bigger or smaller depending on how hard you wanna train). Cut off the metal couplers and tape the ends with duct tape. Beats having to pay $150 for one at the sporting good store.