Most people will have grill tanks that use OPD valves. Tanks won’t get refilled without them. If you happen to have older propane valves, you can get adapters to make the older tanks work with more modern appliances. However, the cost to convert older tanks is about the same (if not more) as buying a completely new tank. While cost is an obvious factor in this decision, remember that most gas tanks have a life of 10-12 years. By exploring the most common propane tank connections, you can gain a deeper understanding of their evolution and ensure safe and efficient usage for your gas grill. Until next time, Enthusiasts. As with all things in life, the right connections make all the difference.