SureSTART silver crimp cap for high-performance applications 20 mm made of Aluminum/magnetic tinplate with soft septum 3 mm made of Silicone/Polytetrafluorethylene (PTFE). 100 pieces per pack. As a replacement/alternative for TF20-AC-ST3, TF60180-511. About SureSTART Flare Closures Level 3 High Performance Applications Use Thermo Scientific™ SureSTART™ 20 mm crimp caps with 20 mm opening crimp vials, including our SureSTART 20 ml glass headspace vials with crimp cap (Level 3). Choose Level 3 products for ultimate performance and sensitivity of your methods while ensuring the highest sample safety and integrity. Choose from aluminum and magnetic tinplate caps with general purpose silicone/PTFE septa with various hardness values to reduce problems with autosampler needles. Easily apply and remove crimp caps with Thermo Scientific™ manual or electronic crimping pliers and decappers. Features of the SureSTART 20 mm level 3 flare seal ” Level 3 closMeer tonenMinder tonen