People there were very helpful in finding the right pad holder I needed. This one was different than the ones on our other machines.
24 Volt 125 Amp Solenoid (replaces 605905). 
Fits Tennant 1500, 1510, 1610, 5100, 5300, 5400, 5500, 5520, 5540, 5560 B AND Nobles Falcon Ultra B, WB-20, Strive, BA-2000, Speed Scrub 1701 / 2401 / 2701 / 3301 / 2001HDB
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