If you want to put 1/2" pvc pipe and join it with a 3/4" pvc pipe. You would need a pvc reducer bushing to join the two pipes together. Thou they be different sizes
Is that correct?

A better way would be to use a 3/4X1/2 PVC reducing slip coupling, (see image) Check them out at KBI Reducing Coupling, 3/4 X 1/2 In, Slip, CPVC - PVC and CPVC Pipe Fittings - 5UEE8|RCC-0705-S - Grainger Industrial Supply (http://www.grainger.com/Grainger/KBI-Reducing-Coupling-5UEE8)
Good luck, Tom

Thanks a million

If you can't find a 1/2 x 3/4 pvc bell reducer at the local hardware store, you could still use a 1/2x3/4 pvc bushing with a 3/4 pvc coupling. Are you asking about pvc, or cpvc?

Either one would do. Thanks

Not to disagree with Dad but a PVC connection that's cemented is much better then a PVC threaded connection. Same for CPVC. Cheers, Tom

Thanks a million. I appreciate it

I should have been more clear, Tom. I was referring to a glued bushing and coupling. I agree, glued is better with plastics.