The Chelsea 37P25 is a return spring and shifter spring used across multiple Chelsea PTO series. Listed in the illustrated parts manuals for the Chelsea 100, 381, 436, 438, 440, 441, 446, and 488 Series power takeoffs, this spring is a direct-replacement service part for those units. Depending on the series, it functions as the return spring or shifter spring – one spring per unit as specified in each manual. Call us to confirm proper fit for your specific PTO model and application.FeaturesGenuine Chelsea part number 37P25Functions as return spring or shifter spring depending on PTO seriesFits Chelsea 100, 381, 436, 438, 440, 441, 446, and 488 Series PTOsOne spring per unit as specified in the Chelsea illustrated parts manualsDirect OEM replacement service partUsed in these Chelsea PTO models100 Series381 Series436 Series438 Series440 Series441 Series446 Series488 Series