[pizzainthemorning]

So I'm wondering, is there any real difference between a windowed (where you can look in and see the spring/piston) gearbox and ones without? I was checking out WGC and they had stock TM gearboxes, both Ver. II, except one was windowless and the other windowed, saying that the windowless one was for G3's and Mp5's, windowed for M16A2 and M4's. Is this really critical? Like will any version II gearbox fit the bill (so long as it's made by a compatible brand)?

The other question is about where they list the gearbox as 6mm or 7mm for bearing size. Do you need different gears to fit with the 7mm size? or is that the point, so it's loose? What size is "standard" 6 or 7? In other words, fill me in if you please, I'm ignorant in this.

Thanks,

Alex