VWR Collection Vials with PRE-CUT septa for SPME applications Description Pack Cat. No. Vial screw neck 10 ml, 46 x 22,5 mm, clear 100 548-0247 Vial screw neck 20 ml, 75,5 x 22,5 mm, clear 100 548-0248 Vial screw neck 10 ml, 46 x 22,5 mm, amber 100 548-0552 Vial screw neck 20 ml, 75,5 x 22,5 mm, amber 100 548-0553 New precision thread headspace