2004 Kawasaki ZX636 ZX 636 Ninja 636 Coolant Overflow Reservoir Bottle The Coolant Overflow Reservoir Bottle stores excess radiator fluid to allow for normal expansion and contraction during operation. A used Coolant Bottle will be structurally sound, no leaks, with all mounting tabs and fittings intact. Sample Picture of Coolant Overflow Reservoir Bottle Shown, not necessarily the Coolant Overflow Reservoir Bottle for your bike. You will be shipped the correct part for a 2004 Kawasaki ZX636 ZX 636 Ninja 636 Click here to see other parts for your motorcycle Kawasaki Model Identification Note: On all Kawasaki models produced after 1980, the 7th digit of your motorcycle's VIN (it is a letter) is critical in identifying the model of motorcycle you own. For example, if you own a 2000 ZX6, and the 7th digit of the VIN is an E, then you own a 2000 ZX6 E; If you own a 2001 Vulcan 1500, and the 7th digit of the VIN is a G, then you own a 2001 Vulcan 1500 G. Please confirm the 7th digit of your VIN number before placing your order.