Andrew Mollo, "Uniforms of the SS - Volume 5 - Sicherheitsdienst und Sicherheitspolizei 1931-1945"
Historical Research Unit, London | 1971 | ISBN: none | 54 pgs. | PDF | 22MB
If you have the previous so-called "scan" of this book, delete it. It was missing many pages, was low quality, and did not have the (tiny bit of) color of this scan. The original printings in the 1970s of this series had color in some of the plates which was omitted in the 1990s reprintings.
As for this book itself - the Sicherheitsdienst was not very numerous and didn't have a wide variety of uniforms or insignia. It included the Einsatzgruppen whose mission was plain mass murder. The Sicherheitsdienst of the SS did have a complex organizational structure which Mollo tries to explain. The last part of the book tells of the locally raised police and security auxiliaries raised in eastern Europe.