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The first very first 12" single was released in 1973 by soul/R&B musician/songwriter/producer Jerry Williams, Jr. aka Swamp Dogg. 12" promotional copies of "Straight From My Heart" were released on his own Swamp Dogg Presents label (Swamp Dogg Presents #501/SDP-SD01, 33¢..." r.p.m.) with distribution by Jamie/Guyden Distribution Corporation. It was manufactured by Jamie Record Co. of Philadelphia PA. The B-side of the record is blank.
The first official promotional 12" single was Southshore Commissions' "Free Man". At first, these special versions were only available as promotional copies to DJs. Examples of these promos, released at almost the same time in 1975 are, GARY TOMS EMPIRE - "Drive My Car", DON DOWNING - "Dream World", BARRABAS - "Mellow Blow", THE TRAMMPS - "Hooked for Life", ACE SPECTRUM - "Keep Holdin' On", SOUTH SHORE COMMISSION - "Train Called Freedom", THE CHEQUERS - "Undecided Love", ERNIE RUSH - "Breakaway", RALPH CARTER - "When You're Young and in Love", Michael ZAGER & The Moon Band Feat. Peabo BRYSON - "Do It With Feeling", MONDAY AFTER - "Merry-Go-Round", THE RITCHIE FAMILY - "I Want To Dance" and FRANKIE VALLI - "Swearin' to God".
By 1976, with the release of "Ten Percent" by Double Exposure on Salsoul Records, the new format was sold to the general public. The second song found on a 12" single is "Love to Love You Baby" by Donna Summer, released in 1976. This song was originally a full side of her North American debut release, but released again in early 1977 backed with "Try Me, I Know We Can Make It", on the Oasis/Casablanca label.