You use them to align the flippers. Push em up, adjust the flippers, back down for gameplay.

Those are called roll pins . They are used to line up the flippers
I left mine out on my TOM swap ,personal choice .
I didnt want to damage the new playfield by hammering them in.
If you do use them, drill pilot holes. Use a NEW drill bit that is slightly smaller,so its nice and snug.

I would save them. They are a nice and easy way to help with flipper adjustment.

*Edit* after the discussion in this thread, I wouldn't suggest putting them back in a new playfield. When I read the op's question I missed the playfield swap part.

U sure your supposed to move them to adjust flippers? I thought u just used a toothpic or small Allen wrench in the hole

They move up and down easy. You can also use the pick or allen. It's all good either way.

Interesting ive never encountered a easy moving one

Ok, you tell me. Why the heck would they bother to put roll pins in there if they weren't supposed to be moved? I mean lots of games had the holes, but no pins.

And why would you need a hammer to move a roll pin?

So u can put a tooth pic or something similar in the hole I imagine? Ive seen people try hammering them and it damaged the play field by chipping it topside .

Look, back to the original question. Those pins were installed at the factory for the purpose of adjusting flippers. You can still use them to do that. I've yet to see one that needed a hammer to move. If you don't want them to adjust your flippers don't use em. I happen to like games with them. I push em up, usually use the handle of a nut driver, adjust my flips, and push them back down.

Roll pins are smashed on the ends a little so they stay put same thing the plugers use to hold tips or other things in place. I also use the alot on my gun builds so im pretty sure they sldnt move without a correct size punch .

What moron did you see hammering the bottom of their playfield? I hope you smacked em.

Then use a punch not a hammer. lol

If you look in his pic in the first post u can see they splintered the wood below when installed ive seen that on the topside from people that pushed them up but I guess if done correctly like u have did it sld be fine im not trying to say there is no right or wrong just alot easier and safer to use a small allenwrench tho

I think we got off track here. Obviously if they don't move easy you shouldn't force them, especially on a new playfield. The fact remains though, they were originally there for flipper adjustment, which was the initial question. Now Leo13 is right, I wouldn't bother putting them in on a playfield swap. On in old playfield however I find them beneficial and have never had an issue moving them up and down.

Definitely there for flipper adjustment no doubt about that and I love them and use them alot .I think the roll pin was used bc just a bare hole there's a chance when tightening the flipper that the wood gives and can put a indentation on the edge of the hole or much worse chip or splinter the playfield depending on what is used in the hole , also its alot more accurate with metal than bare wood bc it wont give at all.

No argument here.