[A/S] Tanks and valves

[a9464@xxxxxxxxxxx]

I have a pair of 40 lb. alum propane tanks. I can use them this year, 
but will need to refit them before next season. Mine have valves that 
are equiped with fuel level gages. A small half dollor sized circular 
gage that tells the propane level in the tank. First... are these 
gauges mechanical or do they read internall preasure? and more 
important, has anyone seen the new valves so equiped? And if so, 
where can I buy them. I like the gauges because the tanks are to 
heavy to take off and weigh.