Dual Barrel Syringe Gel Dual Barrel Syringe Gel 1.3.5ML, 25% or 35% high quality import gel 2. used for 2 patientDual Barrel Syringe Gel 1. Dual-barrel Syringe of Teeth Whitening Gel2. with a mixing tip3. will mix the gel accordingly when you push the syringe4. very convenient to use,no need to mix by hand5. can be sealed when you do not use,keep long activity of the whitening gel