Udor 6061.28 Seal Kit with replacement 18mm seals for popular Udor pumps like the B Series and M Series. This kit includes three 18mm plunger seals. All seals are OEM parts. The following pump models can be serviced with this seal kit: BC 13/20 S, BC 15/20 S, BC 18/20 S, BC 21/20 S, BD 4.0/20 S, BD 4.0/30 S, BD 5.0/30 S, BD 6.0/30 S, BKC 15/30 S, BKC 18/25 S, BKC 21/25 S, BKD 5.0/36 S, BKC 21/25 T MI, BKC 15/30 GR, BKC 18/25 GR, BKC 21/25 GR, BC 18/20 GR, BC 21/20 GR.