How about the more common boston valve. Most of us have heard this name before and most of us have used these before you just might not have known it. The boston valve is a one way valve with 2 caps and 3 parts. The parts are the attachment to the bladder, the middle cap to remove all air and the top cap for filling the bladder. To work these simply pop of the top cap and use a foot pump or double action pump to inflate your tube. To deflate with the boston valve you can pop off the lower middle cap and remove all the air very quickly. This is great to help with quick deflation of your tube for storage. It is not recommended that you release the middle cap while on the water as this could lead to complete deflation of the tube which would put you in a situation that might not recover from. I say this because I have seen this happen while on the water, it worked out ok in the end, but any other situation this would have been a much different outcome. Most all pump types will work on these valves and they just work very well. One of the best parts of this valve is that you can replace at least the middle and top sections of the cap. I will be honest I have not come across any downside to these valves, as I said they just simply work.
Halkey-Roberts Valves, so I am learning that there have been some new models of the Halkey-Roberts Valve. So if you have an older version on your tube you cannot simply buy a replacement cap you will need to replace the entire assembly including what is on the bladder.
The Halkey-Roberts valve has been around a while now and is a great alternative the the more basic valves. It is assumed by some that this valve is a pressure relief valve. Not all Halkey valves are pressure relief valves but it looks as though you can upgrade if you see the need for this. The pressure relief is a great idea while in the water as you can easily remove the buildup of pressure on a hot day without risking completely deflating your float tube while on the water. Some people may see this as a downfall and I agree,see you will need a special wrench to open and close the valve. The downside is obvious don’t lose the wrench or you will be unable to fill or quickly deflate your float tube.