Check the listing for details. Traxxas 5381X Differential Spool (Front/Rear), Revo. Condition: New. Listed at 12.00 USD. New in package Traxxas 5381X Differential Spool (Front/Rear), RevoThis is a optional Traxxas Differential Spool that replaces the differential gears and is intended for use in place of the front or rear differential with the Traxxas Revo, and E-Maxx Monster Trucks. This spool eliminates the differential and locks the axle, providing equal power distribution to both wheels. This part is for off road use only and is ideal for straight-line sand drags, rock climbing, or pulling. You can replace both the front and rear differentials with spools for total 4WD traction. On tight off-road tracks, installing a spool in the rear diff case allows the rear end of the truck to rotate more easily and slide through the corners. The spool's corrosion-resistant finish and tough steel construction ensures lasting durability.Notes: Spools cause extra stress to most of your driveline components, so only use spools in low traction conditions to avoid accelerated drivetrain wear. This spool requires #5379X ring gear. (Sold Separately)Features: Optional Upgrade Corrosion-Resistant Finish Tough Steel Construction Lasting DurabilityIncludes: (1) Differential SpoolWe will combine shipping, just 50 cents more for each item.Vehicle models vary. We DO NOT guarantee this will fit the vehicle specified in this listing!Verify that this item is appropriate for your vehicle. Consult your manual or vehicle manufacturer.Verify vehicle fit-ment before purchase.Returns will only be accepted on items that are returned in new, factory-sealed packaging. Used, damaged (unless damaged when it arrived to you), and opened items will not receive a full refund. Any and all warranty claims will be handled through the manufacturer directly.