Background: Glioblastoma (GBM) is the deadliest and most common brain tumor in adults. with poor survival and response to aggressive therapy. Limited access of drugs to tumor cells is one reason for such grim clinical outcomes. A driving force for therapeutic delivery is interstitial fluid flow (IFF). https://www.bekindtopets.com/flash-deal-Cat-Punch-Ball-Toy-with-Scratch-Base-on-sale/