>>54908
This is not a "screw" to fasten stuff, this is a "screw" just to apply some pre tension.
That's why the proper "tool" for this "screw" is made out of plastic and the only torque on it is applied from the palm of your hand.
FFS Bert!

>>54910
Wait, this failure mode is even worse:
Did you remove the crank arm without removing the tensioning "screw" first?
WFT Bert!

>>54914
Bert... this little thing (4) is not preventing anything, it is just an indicator so you know if the crank arm is "deep enough" on the axle.
Well, Bert... have you read any manual before hand?