On this day in music history: March 31, 1949 - RCA Victor Records releases the first commercially available 45 RPM record available for domestic sale. That first single is “Tekarkana Baby” by country music legend Eddy Arnold. Written by Fred Rose, Arnold’s version of the song will top the Billboard Best Selling Retail Folk Records chart (existing prior to the Country & Western chart) for one week. The label will press the initial run of the single on clear green vinyl. RCA will develop the new format in response to Columbia Records introducing the 33 1/3 RPM longplaying LP the previous year. Pressed on vinyl (or styrene) rather than the fragile shellac discs that 78’s were manufactured from, the 7" discs will grow in popularity, eventually overtaking the 78 in sales by the mid 1950’s and becoming the dominant single format until the end of the 1980’s.