Travel to Canada for 7 days with approved h4 but not stamped

[ManaviS]

Hi I have an approved h4 and h4 EAD, but the passport is not stamped, still have my old visa stamped, I read there are exceptions to travel to Canada + Mexico ( less than 30 days) and we don't need to get visa stamp and can re enter the country showing our new approved h4 i 94, was hoping I can get a confirmation on the same.  Also my husband is carrying his employer letter do I need to carry anything? 

[newacct]

Yes. It's called Automatic Revalidation. You can re-enter the US after a trip of less than 30 days to Canada or Mexico, if it's before your previous I-94's expiration date, even if your visa is expired or it's the wrong type of visa.