Headspace Vials, 18mm, 12mL vial, glass Aijiren Tech™. Unlike crimp cap vials, require no tools for closure. Manufactured with superior quality (Type 1, Class A) glass, they are available with a round bottom in sizes with usable volumes of 10mL or 20mL. The 18mm vials feature Magnetic Screw Caps which enable magnetic pick up in autosamplers with that capability.