NuTone® 391C 6-gallon disposable central vacuum bag (3 per pack) double-ply. The bag traps particles as small as 0.10 microns, at an efficiency rate of 85%. The bag is compatible with the following central vacuum power units: CX450, CV654, CV353C, 353C, CV653, CV400C, CV750, CV352C, 352 CV, 350C, CV350C, CV450C, BQ1, BQ2, BQ3, BQ550, BQ650, BQ700 , 500VF, 600VF, 650VF, BQ500KIT, NCKIT1000, NCKIT3000, NCKIT5000, NCKIT1000HD, NCKIT3000HD, NCKIT5000HD, NC4000, NT600E, NT650E, NT650A, HHKIT500A, 00E, HHKIT600E.