This is a set of 4 absorption canisters for organic gases. It does not have dust-proof function. This listing is for the canisters only. The facepiece is sold separately. Please check the expiration dates as they vary before use. [Compatible Gases] Toluene, benzene, xylene, cyclohexane, trichloroethylene, etc. *This does not remove all organic gases. [Compatible Masks] TW01S, TW01SC, TW01SFC, TW02S, TW08S, TW08SF, TW022Sd, TW088, TW099 [Effective Time] Varies depending on gas concentration. Example) Cyclohexane concentration 0.01%...300 minutes 0.02%...150 minutes 0.03%...100 minutes [Expiration Date] February 26, 2026 (unopened) 3 pieces April 29, 2026 (unopened) 1 piece