What you see is what you get
Let's have a look at the HSe-221. It has a shrink ratio of 2:1 which means it will half in size. It's rated at a size of 8.8mm, but what does that actually mean?
When flat, the tubing is 8.8mm in width. To work out the diameter of the tube when round, you need to times it by two and that will give you the circumference. Then divide that number by pi. Width of tubing while flat: 8.8mm Circumference of tubing while round: 8.8 x 2 = 17.6mm Diameter of tubing while round: 17.6 ÷ pi = 5.6mm Diameter at a 2:1 shrink ratio after shrinking: 5.6 ÷ 2 = 2.8mm So if you have a HSe-221 cassette, this tubing will be suitable for a cables with a cross-section of 2.8mm to 5.6mm.
For any further help with heat shrink tubing and choosing the correct size, please feel free to call us on 01202 681311.