Thank you for the reply!

Im using #000 for the most part sometimes bigger ones but it doesnt matter because i cut them down so that it's just around the card(s) and then tape it up to remove any excess weight.

Going on that site the cheapest option it gives me is

First-Class Mail® International Parcel (0 pounds 2 ounces) $3.15 which is what I pay usually but can't find the less than $2 option.

Maybe the lady who is putting it into the machine is doing it wrong and that's why it's cheaper sometimes?

Maybe the lady has her finger on the scale! I caught the postal lady at one of the outlets I used to use doing this...I send everything light package with a customs forum in Canada. under 100 g its $2.80 (with HST) I think its double that up to 200g then I use Small package air $7 or $8 I can't remember the exact price. The thing that gets me is that when I get stuff from the USA or send from Canada it takes sometimes 7-14 days or more to reach its destination sometimes longer. When a package sent from Europe gets here in 3-4 days whats up with that!