100% compatible with CPAP machine Quick install and easy to use Recommended 6-month replacement: It is advised to replace the filter and valve every 6 months Universal compatibility: Filter replacement kit features an exquisite design, perfectly compatible with SC1200 and SC2 machines, delivering the same performance as Convenient to install: CPAP filter kit replaces old or damaged filters, easy to install without additional tools and without risk of leakage Easy to carry: CPAP machine filters are small, lightweight, and convenient for travel Material: Plastic Color: Grey Package contents: 6 x Filter 6 x Check Valve Assembly Only the above package content included; other products not included Note: Light reflection and different displays may cause slight color variation between the item and the image. Measurement error allowance is +/- 1-3 cm