While participating in a TOT for my AOA camp this past January, I saw these nifty weights. They are made from recycled materials, including KLIM cans, PVC pipe and concrete. Once I returned to my own little jungle home, I got to work creating a pair of weights. You can also use PB jars or another sturdy container. Fill up the container with rocks. Cut a hole in the plastic lid, just big enough to push a pipe through. Half inch PVC pipe fits perfectly in your hands! Create concrete using a 2 sand:1 cement ratio and some water. Pour the mixture inside the cans and fit the pipe in snuggly. Push the lid over the pipe, down onto the can, and secure shut. Let dry then do the other side. You could make a set but I just made one and alternate reps between my arms. This nifty craft is a big improvement to my previous weights- Game of Thrones/Lord of The Rings encyclopedias! How do you work out in the campo?