40ml Vials Use for TOC & Purge and Trap System. With Writing Spot or without. Screw PP Caps, Closed top or with 15mm centre hole. Cap Color: White, Black, Red. Septa: Nature PTFE/Nature Silicone. Septa Size: 22*3mm. 24-400 Sample Storage Vials 20-60ml. Suitable for: 24-400 Screw Neck Vials, 20-60ml EPA VOA TOC Vials.