The Castelli Undersaddle XL is a practical, stylish, user-friendly saddle bag that’s designed to cope with unpleasant wet weather conditions featuring a covered zip and simple, easily adjustable Velcro straps to hold it firmly in place. There’s plenty of room to store multitools, CO2 cartridges, spare tubes and puncture repair kit while a mesh underside allows you to store additional items externally.
Water resistant construction
Adjustable Velcro loops
External mesh pocket
So far so good! Good and valuable saddle bag for the price. I bought the XL size as I wanted to use this for road and mountainbike. I can put 2 road inner tubes+co2 cartridge and valve+multitool keys all safe and clean! It's good for wet rides and it has a nice touch and finish!
A great bit of kit to hold those bits and pieces if you have a puncture and at a great price
Bought as a spare summer saddle bag as I use a tool tube in winter. Despite the XL moniker this bag is not very big and would struggle to get more than 1 tube, levers, repair kit and multi tool in it. I'd rather have space for 2 tubes as I have double punctured on more than one occasion in the past. It is pretty discrete though and does have a sleeve to hold a co2 or mini pump on the underside. Good price on Merlin but loses a star for its lack of capacity.