I purchased this so that my family could camp for a full week at state parks that only have electric hookups (I use a Barker blue tote to periodically empty our gray water tank). The bladder goes on top of my Durango, is filled with water, and then I drive SLOWLY back to the campsite. Gravity is then used to transfer the water from the bladder to the camper. The transfer process can be a bit slow perhaps an hour+) but if you're not in a hurry it's no big deal. I love this thing. I've used it many times and it makes transferring a heck of a lot of water a relatively easy and muscle-free event. Some things to look out for... 1. Make sure you have the time to complete the transfer process. 2. Make sure your vehicle's roof is capable of supporting the weight-- 45 gal * 8.3 lbs/gal = 374 lbs of water!

Great for out door showers and rinse off's. With my daughter's hair alone the camper would fillup quickly. Being on the beach, neat way to rinse off sand. We love it and we couldn't go camping without it.