Laboy Glass 10 mL Pressure Equalizing Addition Funnel, Graduated Dropping Funnel with 14/20 Top Joint, Two 2 mm PTFE Stopcocks & Inner Tube, Heavy Wall Borosilicate Glass

Laboy Glass 10 mL Pressure Equalizing Addition Funnel is designed for accurate, controlled addition of liquids in organic chemistry and general lab work. The small 10 mL graduated body is ideal when only small volumes of reagent need to be added dropwise or at a slow, constant rate.Unlike a simple dropping funnel, this funnel includes a built-in pressure equalizing tube that runs from the top of the cylindrical body down into the outlet space below the stopcock. This tube allows the vapor or gas in the receiving flask to equilibrate with the headspace of the funnel, so the liquid can flow smoothly without having to remove the stopper, even under reduced pressure.The funnel is fitted with two 2 mm PTFE stopcocks – one on the lower outlet and one on the side tube – providing precise flow control and excellent chemical resistance. A 14/20 standard taper outer joint at the top accepts a penny head stopper or adapter, while the 14/20 inner joint at the bottom connects directly to a reaction flask or adapter in a reflux or distillation setup.Made from heavy-wall borosilicate 3.3 glass, the funnel is hand-blown for uniform wall thickness and annealed at high temperature to relieve internal stress. It can withstand typical laboratory thermal variations and is durable and reusable for routine synthetic and preparative chemistry.

• 10 mL GRADUATED ADDITION FUNNEL – Small-capacity pressure equalizing dropping funnel with 10 mL volume and clear graduation marks for controlled addition of liquids in organic chemistry reactions.
• PRESSURE EQUALIZING INNER TUBE – Built-in glass tube connects the top of the funnel body to the lower tube below the stopcock, allowing smooth, continuous addition without removing the stopper and minimizing pressure swings.
• TWO 2 mm PTFE STOPCOCKS – Equipped with one PTFE stopcock on the lower outlet joint and another on the side tube for precise flow control and excellent chemical resistance to common organic and aqueous solvents.
• STANDARD 14/20 GLASS JOINTS – Top outer joint and bottom inner joint are precision-ground 14/20 standard taper, fully interchangeable with other 14/20 glassware for easy integration into reflux or distillation apparatus.
• HEAVY-WALL BOROSILICATE 3.3 – Hand-blown from high quality borosilicate 3.3 glass, heavy-wall design, annealed at high temperature to relieve internal stress and withstand typical laboratory heating and cooling cycles.