Compatible with 40H (44250) 40H+ (44252) 40H+ (44253) 40E (44262) 40E (44263) 50H (44600) 50H (44602) Vigör™ HRV Plus (44202) Vigör™ HRV Plus (44203) Vigör™ ERV (44212) Vigör™ ERV (44213) 90H, 190H 60H+ HRV, 60H+ERV Before 2010 units Serial no.: ... up to F?1409 HRV 41600 - 41602 (FA)       (FB) ERV 41604 - 41606 (FC)       (FD) 2010 and up Serial no.: B?0010... and up HRV 41600 - 41602 (BE)      (BF) ERV 41604 - 41606 (BG)       (BH)