Slime Self Sealing Tube 700x28/35c PrestaSlime Self Sealing Smart Bike Tube 700x28/35c Presta. Self-Sealing Smart Bike Tubes with SLiME Inside. All SLiME Smart Tubes are factory-filled with a precise volume of SLiME Tube Sealant. Smart Tubes instantly seek out and seal punctures as they occur, preventing flats, repeatedly and continuously for up to two years. Ride without worries.716281970023