The separatory funnels show signs of prior use. Model: 1000mL & 500mL Separatory Funnel, Squibb, #27 Outer Stopper Neck, 4mm PTFE Stpk. Includes: Three separatory funnels (one 1000mL and two 500mL). This set of separatory funnels efficiently separates immiscible liquids, featuring #27 outer stopper necks and 4mm PTFE stopcocks, making them important for various laboratory extractions and purifications.