Restore proper tension to your mower deck with this high-quality replacement extension spring compatible with John Deere GX25959. This non-OEM part is a reliable and cost-effective solution for maintaining smooth belt operation on your ZTrak zero-turn mowers. Brand-new Extension Spring Compatible Models Include: JD ZTrak Z355E Z375R Z525E Z535R Z540M Replaces OEM Part Number: GX25959 (Non-OEM replacement)