This Zodiac Exclusive .396 US gallon (1.5L) reserve bottle may be the cheapest and best insurance policy you will ever buy. Features a durable ABS cap with a slot for a dummy cord or carabineer that uses an o-ring to stay sealed and safe. At 12 1/8"x3 1/2" (31x10cm) it is the biggest auxiliary container we have found and still easily fits in a saddle bag or backpack. Or go for the fuel bottle with one of the Zodiac-exclusive Texas Leather real leather fuel bottle holders that straps easily to your bike. Also easy to strap to one of the Texas Leather bags with fitted mounting straps.
Note: Made for gasoline, NOT food or water safe!