This Underoos commercial introduced Supergirl to Underoos underwear. This was her first animated appearance. She had previously appeared in the Superfriends franchise in Limited Collector's Edition # C-41 (January 1976), but only as a statue, which makes this technically her first appearance in the franchise altogether. She would later appear in Super Friends # 37 (October 1980), but her only appearances in animation during the Super Friends era was in Underoos commercials, although she did late
Supergirl - Wikipedia
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Supergirl - Wikipedia
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