When a standard size seat bag just won't do, there's Xlab's Mega Bag. Its extra length lets you carry up to two tubular tires or a plethora of tubes and other on-the-road repair essentials. It has two zip side pockets so you can organize and easily access your gear. The bag attaches securely with hook-and-loop and buckle straps. It weighs 79 grams and has a capacity of 84 cubic inches.