LA-CO Slic-tite¨ Paste with PTFE. Specially formulated with PTFE for added sealing power Slic-tite is the premium thread sealant paste. It has been successfully used for decades to seal water air steam natural gas and more. It removes easily from skin and clothing reducing post-job cleanup time. Slic-tite thread sealant works in extremely high-pressure systems and it comes with several approvals to ensure industry standards are met.