7XL or 10L for 16cells

[luihed]

I guess 15 tooth it is.... I was looking at jamies site and all he's got pinion wise are 15 and 16 tooth, where do I get teh 17 or 18 t? also Ive heard of Mod 1 for a while now but Ive never known what it means, how is it diff than a normal 5mm spur?

I think Im ready to make my order mike, do you have the pinions available yet? Thanks