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 & more. It removes easily from skin & clothing reducing post-job cleanup time. Slic-tite thread sealant works in extremely high-pressure systems & it comes with several approvals to ensure industry standards are met.