The last thing you want to do is put those flexible extenders on your valve stems. They have a tendency to leak and if they get loose from the anchoring point they can flop around and not only do damage to your wheel but suddenly deflate the tire.
What is needed is a extended valve stem that will let you quickly check your tire pressure. They add no extra weight like the Extenders would and balancing is no problem.
The best on the market,that are the original,are
Tire Man any others are Knock offs.
This is the set that fit your RVChuck is the original designer of these an he has been around for years. If you have any questions just give him a call, he is always happy to help.
Here is a recent thread on the subject.
On edit: Welcome to the forum from a Retired Teamster.