Single Edge Blades?

[MetroNome]

Today at Bed Bath Beyond, I saw single edge blades. Are these used in some sort of special razor?

 

[Omnichron]

they're used in single edge razors like this one

 

[relaxandshave]

Yep, a special razor that's only second to a straight edge. As Omnichron mentioned, they're used in single edge razors such as the Gem Junior, pictured, Gem Micromatic, and various other models made by GEM, Star, and Ever Ready.