Crafted from the highest quality glass, these concentrate syringes are the best on the market! Borosilicate glass is heat resistant, sturdy, and the clarity is unmatched by cheap imitations. What makes this syringe so awesome? Graded capacity on the side makes dosing simple and accurate (0.5 gram and 1 gram), the silicone leur slip cap provides an air-tight seal and prevents leakage, and the silicone-tipped push rod ensures every last drop of oil is dispensed. Plus, sterile packaging ensures your syringes are clean and ready-to-fill.