This is a A-B1AF199 AIR FILTER, HILTI 261990 PN: B1AF199Main Description As Following : A-B1AF199 AIR FILTER, HILTI 261990 P.N: B1AF199 Replaces: 261990Size: 4-13/16" L x 4-1/8" W x 1-7/8" H Crossed From: 261990 HILTI , 605-712 STENS , 605712 STENS Found in Section & Models : Sunbelt - Air Filters > Air Filters, (Miscellaneous) (UNDEFINED): SEVERAL Associated Items : New Also This is An Aftermarket Product And : Replaces: 261990 Size: 4-13/16" L x 4-1/8" W x 1-7/8" H