Nice build. The Whisker is a toothbrush, I also like how the author bends the handle.
http://www.instructables.com/id/PVC-Slingshot-Bow-With-Homemade-Whisker-Biscuit-Vi/
The author also had an origninal build here that this is based (and improved) on
http://www.instructables.com/id/PVC-Slingshot-Bow-V-20-With-Shooting-Demo-Video/