- Headspace screwtop 20mL clear vials100pk $87.70 Quick View 5188-2759 - UltraClean 18mm screwcap w/septa 100pk $157.00 Quick View - Screw vial,10 ml,CTC Hdspce/SPME,100 pk $76.90 Quick View - Headspace Screw vial, 20ml Amber, 100/pk $123.00 Quick View - Headspace Screw vial, 10ml Amber, 100/pk $110.00