Flat tops are fine, http://www.fasttech.com/products/0/10001980/1141100-panasonic-ncr18650b-rechargeable-3400mah-3-7vDo I use button tops or not?
My Orbtronic 3400 protected cells are way too tight to fit in mine.
This has been mentioned before and I think it was concluded that orbtronic cells use a protection device which is in fact larger than what the specs state.
As far as I know both the Orbs and Zebralights' own 3400mAh cells are the same cell. That leaves the skin or protection circuit at fault for it not fitting. I haven't got my SC600 Mk2 and I didn't order the ZL cells but I have no doubt the cells I do have and the cells they can supply will have no fitment issues.
My Orbtronic 3400 protected cells are way too tight to fit in mine.