Shrink Tubing plays a big part in modern angling. 
Shrinking sections down over hook eyes to create a specific angle or kicker to a rig. Covering swivels, e.g when connecting a hook to a Ronnie Rig. Even using a small section to trap a hair for a classic hair rig.
 
Its available in 4 colours - 
Black, Clear, Brown & Green 
 
In either -
1.5mm
2.5mm
Diameter, pre cut into 6cm pieces.
Available in packs of 10, 20 or 40pcs