For items up to 26cm x 36cm,
AND MOST IMPORTANTLY ONLY UP TO 2cm THICK:
$1 FOR 0-125GM
$1.45 FOR 125-250GM
$2.45 FOR 250-500GM
ANY MORE THAN 500GM IS CLASSIFIED AS A PARCEL AND SO PARCEL CHARGES WILL APPLY.
ANT THICKER THAN 2cm, it is a parcel, even if it is 50gm! so it may be cheaper to sometimes get a larger envelope and spread the cards out rather than tape them all together (esp since bubble also adds to the thickness) and stick them into a tiny bubble envelope.