The PR Bobbin from Shimano is strong, lightweight and simple device that can achieve stunning PR knots and binds with ease. It comes with a built-in line tensioner as well as double O-rings to lock in your braid, preventing slippage during your winding. It also features a hard zirconium ring at the tip that reduces heat and friction by allowing the braid to run smoother under tension.
Sizes - PE0.3-3 PE1.5 - 8 
Type - Bobbin Tool