Jocelyn if you're running this, how accurate and what decimal place can your scale weigh up to? At a minimum, you'd have to have something that can weigh to a hundredth of an ounce since you're dealing with ounce fractions. Ideally, you'd want something that is accurate to 1 thousandth of an ounce, but those are expensive. This is important because these lube are very expensive for the amount you get, so every drop counts and must be measurable.
For reference, a quarter ounce is only about 7 gram. If your scale is accurate to the hundredth, that translates to +/- about 1 gram. So if you're shipping out quarter oz, one bottle could have 6g, one could have 8g. Someone could potentially have 33% more than the next guy. But of course if you're doing them in half oz or full 1oz, the difference is less noticeable, but you're still paying by the drop.
