You can obtain a seal using PTFE< but you would be better off with a running nipple and keeping the thread forms consistent.

At the other ends, if the fittings you are attaching to have a flat face inside you can use a fibre washer, if not ptfe tape again. Adapt our new style stainless steel hose reel inlet to a ¾ inch thread with this 3/4 to 1/2 reducer.

The last time I used it was on a running coupler around four decades ago, about the only time you encounter parallel male thread on a piece of ordinary iron pipe these days.

I have tried using PTFE tape (dad did have some in the late 1960's), but my experience was that there is a knack to applying it to make sure that it doesn't get pushed out to the exposed part of the thread and leave an unreliable seal. My understanding is that, for general purpose iron pipes and fittings, the modern usual practice is to use tapered male threads and parallel female threads. that dad, a gasworks pipe fitter, used to use in the 1960's) that use meths as a solvent, are generally non-setting and should be removable after a couple of decades without difficulty. Most purchases from business sellers are protected by the Consumer Contract Regulations 2013 which give you the right to cancel the purchase within 14 days after the day you receive the item.

It doesn't specify the thread but looking at it now it looks parallel but as its half eleven I am not going to get a fitting to screw into it tonight. Thread reducers and adaptors are essential components in plumbing and piping systems as they allow for seamless transitions between different pipe thread sizes or types. With a smear of compound applied to the inside of the female thread and a smear applied to the end of the male thread , you can be sure that compound will be present over the entire surfaces of the mated threads of the two parts.