#50 X 59 PITCH CHAIN. COMPATIBLE WITH PART NUMBER 4172864-01. FITS THE FOLLOWING CLASSEN AERATOR MODELS: SA-30 SN 0000 THRU 0299 -STANDAIRE PRO, SA-30 S/N 0000 - 0124 STANDAIRE PRO, SA-30 S/N 0125 TO PRESENT STANDAIRE PRO , SA-30 SN 0125 AND UP -PRO STAND-AER SA-30A SN 0300 TO 0420-PRO STAND-AER, SA-30A SN 0421 TO 0447-PRO STAND-AER SA-30A SN 0448 THRU 0506-PRO STAND-AER, SA-30A SN 0507AND UP-PRO STAND-AER SA-30ACA SN 0000 TO 0100-PRO STAND-AER, SA-30ACA SN 0101 TO 0101-PRO STAND-AER SA-30ACA SN 0101-PRO STAND-AER FS541V AND SA-30ACA SN 0102 AND UP-PRO STAND-AER.

Warning:Lead-Nickel-Cancer and Reproductive Harm