These 4 - pack clear glass trumpet vases are great for wedding table centerpieces. First, before using them for the first time, you should wash each vase by hand in warm soapy water. Rinse them thoroughly and dry with a lint - free cloth. If you want them to look their best, clean them with a 50/50 solution of vinegar and water. Let the solution stand in the vase for a few hours, then rinse well and dry. Remember, there's a block halfway into the vase, so you can only put things halfway into the base. Also, because these vases are made overseas in large quantities and stored in bulk, they might have some dust on them. So, always clean them before use. And don't clean them in a dishwasher or use them in microwaves or conventional ovens.