:doh: @stonedmallone
£4.32 | 5pcs High borosilicate glass tube,O.D. 16mm,Thk. 1.5mm/1.8mm,Full length 200mm/250mm/300mm,High temperature resistant glass tube
https://a.aliexpress.com/_mKrm0fW
I use the 100mm but I bought 200mm as well, just for shits and giggles. They work but are comically big.