Is there such a thing as a metric Phillips bit?
 

0 seemed too small and #1 too big. Someone who I thought should know said it was metric. I did a search and I did find a reference on a RC forum but that is it.

Here is some description of various screw drives:

List of screw drives - Wikipedia, the free encyclopedia

There are Japanese bits called JIS, IIRC. They look similar to Phillips, but internal design is slightly different.

ETA: there are also posidrive bits, but they are used more in Europe.

I stumbled upon a 3.5 mm fastener last year and found I had a 3.5 box that was in a set I've had for decades but never used, didn't even know I had it.

Check the Wiki link... I bet it's a Pozidrive.

Pozidrive or the stupid Phillips head with a square in the middle. A combination drive that allow a sq drive to be use to prevent cam-out. A Phillips driver will work, bur slips often. I still think its Pozidrive.

it is not a pozidriv or even that French drive in the wiki link. I can't find any reference to anything outside the range of #000 to #4.

It is a small screw with Locktite that is difficult to remove. A new #1 bit will get it out. I think the guy just made the metric bit part up.

Look up JIS. A Phillips will usually fit a JIS style screw, but it's better to get the bits from some of the Japanese toolmakers.

Metric Phillips? Would that be a "Philippe" bit....

HAHHAHAHAH. That's funny.

If it has loctite on it, can you heat it up, or would that damage the piece"

Can you take a photo of the head with something next to it like a coin?

This has me very curious. I'm very fussy about screw heads and I always use the correct non worn screwdriver tips to remove them. Generally tips/screwdrivers by Snapon or Starrett are the best fitting.
My ultimate goal is to remove and reinstall them without marking them.

(One of my hobbies is repairing old film cameras and lenses)

Heat the head with a soldering iron.

I sold a Metric Crescent once. To a girl that was looking for one.

Frearson?

Sounds like the JIS. is what I found on a fan this summer. Tried several different bits to undo them. Ended up using a BFH to smash it to pieces. BFH's work best on all screws types. :)

I looked at them again compared to another Phillips along with a Google search and I bet it is a Japanese Industrial Standard (JIS) Screw. How it ended up here is another question but the thing does have its origin in the Pacific rim.

The Phillips heads are different on some screws. If you look at the bit, some are more angular and some not so much. A new bit will cam out on you if use with different Phillips slots. The slot on a drywall screw and the typical sheet metal screw are slightly different. Love to see a pic because it is bugging the hell out of me not knowing what it is?

I have used these thing before with some success. How big is this screw? Sears.com