Peggy,
You have gotten a lot of good information from members. I'll add something else. I took my nylon drain plug out of my heater in my Winnebago & replaced it with a flexible, metal mesh hose made to be used on any home sink faucet. You can match the thread size of your plug for an exact fit. They are made in several lengths. I bought one that would fit inside the heater compartment and added a hand shut off valve to the outer end of the hose. This allows me to drain the water heater easily and completely any time I want or NEED to, like if a smell develops in the hot water, and when cleaning the water system in every spring or after getting bad water of any kind while traveling, and to winterize the system each year. I installed this 11 yrs. ago and have helped friends install one in their motor homes several times.
Once this is installed, you don't need any tools to work on it. If you have ever filled your water tank while on the road and gotten water that is not good in any way, as I have, you will be glad to have this to help clean out the system.
TRY IT! YOU'LL LIKE IT!
Wayne