M-bag surface mail travels the same way that regular surface mail does and is in the same class of service, so it is important to alert your customers that you are shipping this way so that they have realistic expectations.
M-bag air mail travels as first class mail. If you are using the M-bag air mail service be sure to tell the post office to put your package in the green air mail bag and to label/stamp it "air mail" generously. On more than one occasion, we have paid for air mail service, but because M-bags are always shipped in brown boxes, or boxes covered with brown paper, they are sometimes mistaken for surface mail.
There are two main disadvantages to M-bag service: it is not trackable, and it is not insurable by the post office. You can, however, purchase a "Certificate of Mailing" from the post office, which proves that you put the parcel in the mail, at a nominal cost. To insure M-bag parcels, use a blanket or one-time-only insurance policy from a carrier such as u-pic (www.u-pic.com) which covers all shipping nicely. If you are trying to send a package to a country that u-pic doesn't cover, you may wish to reconsider filling the order. They do not cover countries that have less than an 85% completion rate, or obvious global hot spots.
As soon as a parcel weighs over 4 lbs. we always consider sending it by M-bag. To compute the amount of postage for an M-bag parcel, do the following:
Go to www.usps.com
Select Calculate Postage
Select Calculate International Postage
Select Calculate Volume Discount Mail
Select International Volume Discount Mail
Select the country from the pull-down list (continue)
Select Economy M-bags (Books and Publisher's Periodicals) - do not select "Economy M-bags" as these non-book rates are higher, or Airmail M-bags if you are sending the books air mail (continue)
The Pieces field is a multiplier; if you are sending only one package in the bag, leave it at "1"
Type in the weight of the parcel to the nearest pound
