I'll have to admit I didn't know this. Not all screws are the same it would appear - as I was to discovered to my cost. Many of the smaller ones, holding the float bowl of the carburetor for instance are JIS, Japanese Industry Standard. At first glance you would swear (I know I did several times) that they were standard Philips. The giveaway is a tiny dimple or punch mark on the screw head. A Philips driver will fit but it is more likely to twist out or mash up the head. The JIS driver is slightly different in profile and less prone to slipping. Just thought I'd pass this on as I learn from my mistakes.http://www.webbikeworld.com/motorcycle-tools/jis-screwdrivers/

Just cleaning out the fuel pump and discovered just how well these screwdrivers fit. Bet a Philips driver couldn't do this.

Yes I knew about these but to be honest if you just grind a Philips down till the sides are flat then you get the same effect. Most of the problems folks have is due to worn tools. I have some spanners from when I was an apprentice at 16 still as good today as they were then but I have no screwdrivers from then cos they wear out..! Most screw heads are fucked when you try to take them out not when you replace them, if your careful and clean the heads out before you tackle them most of the time that is enough. J.I.S. and Philips are not the same but I'm pretty sure I can get a "new" Philips to do the same as your J.I.S.

Have been looking at this recently as saw an article about it on the web. I was going to get some of the screwdrivers of ebay but they were quite expensive but found a dealer who does the "Motion Pro" tools here in the UK and they do the packs of JIS bits in the #1,#2 and 3# sizes as here 

http://www.dirtbikebitz.com/motion-pro-tool-jis-cross-bit-2pk-p-76638.html?gclid=CPyihtz03dMCFaa17Qod3BMLqg&utm_campaign=products&utm_medium=BaseFeed1&utm_source=GoogleBase1

Also after a bit of research on the web found out that Tamiya who do the R/C model cars also do their own screwdrivers that are JIS Standard but only in #1 and #2 sizes.

Tony