As we haven’t got a Fairphone Support article about this longstanding issue, I have cobbled together the little that is known. If you can add information, please do so, but always cite a source and make your links as precise as possible.
|FP1||Phillips #000||3.9 mm / 2.5 mm||?||iFixit (steps 7 & 17)|
|FP2||Phillips #0||5.5 mm||1.4 mm||iFixit (step 6), Forum|
|FP3||Phillips #00 (or #0)||3.8-4.0 mm||1.4mm||iFixit (step 5), Forum, Forum|
|FP4||Phillips #00 (or #0)||4.5 mm||1.4 mm||Forum|
For potential sources (where to buy), see these topics: