Simon,
It depends on which your 914 originally had for Shocks & Struts/Inserts
All Springs were black AFAIK,
Boge Shocks/Struts/Inserts were black or dark gray,
Bilstein Shocks/Struts/Inserts were kind lime green (yellow nowadays),
Konis Shocks/Struts/Inserts were reddish-orange,
.... & the Koni & Bilstien inserts made for Boge struts were their respective colors, but hidden inside. It was/is common to "upgrade" from the softer stokc base lever Boge shocks/inserts - to either Konis or Bilsteins (KYB are white & stands for Krap IMHO).
Most 914s came with the base stock Boge set-up.
Hope this helps!
Tom
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