I read an article on thunder something.com how to use fish tank gravel cleaner for homemade penis pump clylinders and looked up plastic cylinders and realized condiment bottle would probably work, especially the ones with the tips you can just cut off the bottoms and put your hose pumper part on that. I am going to try this in the near future if I can find any on Amazon exactly 1.5in but if I can't I won't personally try it because I'm switching to only length pumping