Smallest size shrank down to 24 gage hook up wire. Clarity is good. Used my HF heat gun for up to 600 degree heat - keep moving the gun to heat to fully shrink but not burn; point at all sides. Use a hair dryer? - silly, never found one with high enough heat; butane lighter is better than hair dryer in a pinch. No sign of the adhesive that often resembles hot melt glue on inside of tubes or the usual desired bulge out the ends. Shrank well, twisted soldered splice trapped well. Delivery was prompt, no damage. Included storage box was fine and very full.