The new long 3/4" press tailpiece was developed mainly for two purposes: 1) the need for a 3/4" press fitting with integral check valve and 2) to provide an installer extra "lay length" to work with when replacing an old zone valve body, for example.
The Presscon NA10419 fitting assembly is a 3/4" press copper tailpiece with a brass adapter. Our R11217 1" union slip nut couples the brass adapter to a valve body. The NA10419 is perfect for replacing an old zone valve body (any brand) with a Z2 or Z3 Series valve. For example, an NA10419 with a Z2 valve body and a regular press fitting, has an overall lay length of 5" which is plenty of pipe length for replacing any 3/4" zone valve out there.
The Presscon NA10419C fitting is the same, but comes with an integral check valve. The check snaps into the brass adapter section. Our new 3/4" press/check models of 521 Series Thermostatic Mixing valves, for example, use this fitting and so do the new 3/4" press/check models of 132 Series QuickSetter+ low lead balancing valves.
→ Take a look at this short video about our Presscon fittings: