FK/BK are references to names of knots. So FK is forward knot, and BK is backwards knot. So with a FK, you take your 2 strands and make a "number four" shape, and you finish wrapping around and pulling through. A BK is similar, but you make a backwards "number four" and then finish wrapping around and pulling through. When you see them with slashes, it means to do it one way and then the other way.
Fuller-KinyonTM Pumps
fk u fk u fk u
FK Ferizaj was created in 1923.
The tenant of Stadion FK Partizan is FK Partizan in Serbia.
fk u and fk u and fk uuu
FK Smederevo was created in 1924.
FK Lokomotiva Beograd was created in 1985.
FK Pelikán Děčín was created in 1921.
FK Qarabağ was created in 1951.
FK Voždovac was created in 1912.
Laholms FK was created in 1957.