I purchased 1m pieces only (red and black), so I can't be sure. However, let me suggest you to submit a question/request to the 24 hr Support Center (link is up and right side of this page). They should give you the correct answer, and/or take note of your need. Best Regards!
Now I have heat gun for soldering and it works good. Before I bought it I've use soldering iron set at 250 Celsius and touching shrink tube not with tip but with middle part of iron. Worked too. Lighter or matches or candles works too.
Approx at what temperature do they shrink ? Actually I want to buy a heat shrink gun exclusive for this purpose. Wondering if a cheap hair dryer will do the work. Any expert comment is very welcome.
No need for all the fancy stuff mate! A simple lighter or match will do the trick. The small ones only need a second or two flamed and they shrink. Even a candle would in theory do. But candles/matches and some lighters might blacken/dirty the red ones.