This special blue Hollow Pole elastic. Is the strongest in the range. It has a fine narrow bore which prevents flattening out and central core dead areas at the pole-tip end.
  It’s a real strong and flexible diameter yet retains great elasticity.
 3M in length this size 18/20 diameter really is for all day on carp and big fish bagging sessions. 
It's a great favourite and a popular size for commercial waters were constant action and performance is essential, but can still handle smaller fish when needed. 
With it's slightly larger diameter it's still very supple yet robust providing excellent hook-and-hold powers, but still forgiving when striking into smaller fish.
 A terrific all-round match elastic towards the heavier diameter in the range at an unbeatable price.