Ready assembled crimp closures N 11 and plain caps with no liner. Closures available with a broad variety of septa materials and most of them also with different cap colors. All high end (PTFE/)Silicone/PTFE, cross- or unslit septa material has been physically and analytically been tested prior to assembly. Three-layer septum natural rubber / butyl / TEF or two-layer septum Red Rubber / FEP for routine analyses; for more demanding analyses: high purity silicone / PTFE septa. Cross-slit silicone/PTFE septa as a penetration aid for thick / blunt HPLC needles. For all auto samplers transporting vials by a magnet, incl. the CTC PAL, 702879 with a steel (magnetic) crimp cap should be used. To be sealed with MACHEREY-NAGEL manual / electronic crimping tools N 11. A septaless push-on cap N 11 made from PE is available as well (702401).