This is a picture of a composer and double bassist Sergei Koussevitsky. I played double bass very seriously in high school and earlier in college, about 7 years total. I also played violin for 9 years and just started teaching myself the acoustic guitar.
Double Bass bow quiver made from a child's plastic archery quiver attached to E string just above the tailpiece. The quiver rests against the tailpiece itself so shouldn't cause any rattles when playing.