Born To Run original US pressing 7-inch variants (concluded)

Although well-known to audiophile record collectors, it seems relatively less common among casual collectors that Columbia Records were the major issuer/supplier of the styrene-made 7-inch discs in the United States. Back then, using styrene rather than vinyl as an analogue-sound storage medium was probably company's strategy to save costs of manufacturing 7-inch singles. While cost effective and resistant to warp, records made out of styrene are prone to be physically damaged due to its more fragile nature than vinyl. So, it is generally acknowledged that styrene discs tend to wear out in much shorter playing time compared to vinyl discs, with pronounced surface noise and distortion. The deterioration of styrene disc is accelerated further, unless played with the right equipment setting (especially, the choice of stylus is critical).
 

When exposed to a strong light...  From left to right: a stock copy made of vinyl (opaque black); a stock copy
made of styrene (translucent red); and a promotional copy made of vinyl (opaque black).
Note that each photograph was taken of a disc that was kept inside an anti-static plastic bag.

A distinguished feature to styrene 7-inch discs from the US Columbia Records is that these copies are in fact translucent red under particular conditions even though they do look black normally, and Springsteen's Born To Run single is no exception. This "see through" feature is easily examined if a styrene copy is held against a strong light, as shown above. In the US, because styrene was the main medium for Columbia's 7-inch records, the vinyl copies for Born To Run, which are identifiable with the "tall font" sunburst labels, are certainly rare and circulated to a lesser extent than did the styrene counterpart. According to the comments left on 45cat (an online archive dedicated to the magic of the vinyl seven inch single) regarding the promotional copies of the US Born To Run single, these vinyls came mostly from the Santa Maria pressing plant in California, and thus the majority of styrene copies originated from Terre Haute and Pitman plants in Indiana and New Jersey, respectively.

Stamper ring on the white "tall font" promo
label identifies this being a vinyl pressing
(not in my possession)

Interestingly, a copy of the custom white label promotional disc (with mono/stereo version of the track) is found to be made of vinyl, despite that it carries the "normal font" labels (see the picture above). I own two more extra promotional copies and all the three exhibit the vinyl-specific characters: the tapered outer edge and non-translucency with a stamper ring on both sides of the white label. Note that the white "tall font" label version also exists. As shown left, the stamper ring is clearly visible on the record label of such a copy. So, although I'm not sure, it seems that the white label promo copies are exclusively made of vinyl. The preferred use of vinyl over styrene for making promotional disc could be explained by the fact that custom promo copies are usually pressed in a smaller quantity than stock copies (so, using styrene would not save costs effectively). The relative robustness of vinyl against repeated playing would also suit more for the promotional purpose because back then promo records needed to get radio airplay as much as possible. Just my guessing.