Rashi on Genesis 38:18/רש"י על בראשית ל״ח:י״ח

1חתמך ופתילך THY SIGNET AND THY STRING — The Targum renders it by “Thy signet and thy cloak” — the ring which you use as a seal and the cloak with which you cover yourself

2ותהר לו AND SHE CONCEIVED BY HIM (לו, to him) — she conceived men who were strong, similar to himself, and men who were righteous, similar to himself (Genesis Rabbah 85:9).