This is a Marian Martin mail order pattern from 1970. We know it's from 1970 because of the postmark on the original envelope.
It is Printed Pattern 9220 for a button down dress for Misses' size 14.
The paper envelope is in good vintage condition. The paper instruction sheet is slightly yellowed from age but is still readable and usable. The tissue paper sewing pattern has been cut and gently used. We made sure that all the pieces were accounted for and in good condition.