I got my Barska scope out of storage and it was very sticky. It had never contacted any solvents or sprays. I kept it resting on my 50 year old oscilloscope. I tried several things but found that denatured alcohol worked the best. It also removed all writing on the outside but at least it’s not sticky. I found that it was necessary to move to a clean area of the cloth to keep removing and reapplying,