Had an older version of the bag. It’s been my favorite so far. Adding the spray guard is a bonus. It’s a bit flimsy but works.

Awesome the biggest under seat bag very roomy and stylish like the hard look for waterproof bag 5 thumbs up slot of room

This bike saddle bag is great for my Trek mountain bike. Not only does it provide a place for me to store, cash, and credit cards during long bike rides, but it also protects from splashing with the included mudguard. It was super easy to install and took it less than 10 minutes to install/setup. I definitely recommend this bag for any avid biker!

Update 03/11/24 - After ride experience, love it - works perfectly. Original review follows:First impression, WOW this is a home run.Overall Construction: This bag is semi-rigid. It has zippers providing access to two separate compartments. The left side is the main compartment and inside is a mesh bag which is permanently attached. It also has a full length zippered pocket. The right side is much shallower and has numerous pockets of various sizes. Some of the compartments have elastic and some don't (no zippers inside this compartment). There's enough storage here to please just about anyone.The mud flap is very flexible and is easily removable when not needed. I like the flap's flexibility because at speed it should straighten out and minimize drag. The bag is also fairly narrow (still has plenty of room) which should help minimize drag and keep it out of the way of pedaling.Installation. First job is to figure out how to mount the mud guard. There are no installation instructions (which is my only nit) so pay attention to the vendor's listing which clearly shows you how to do it. Once you've worked your way through the process - it makes sense. The slots in the bottom allow you to either mount the mud guard a little forward or a little back - there are 3 slots in the bottom and you'll use 2 adjoining slots depending on where you want it positioned. The next step is to secure the mount under the seat which is tightened using a knob. Once the mount was secured I temporarily placed the bag on it and adjusted the angle of the hangar (they include an Allen wrench to do this). I then fixed the cant of the bag by tightening a single screw. The final step was to thread the strap through the front of the bag (pay attention the smooth side will be facing away from the bag when threading) and then wrap it around the seat post. Done. Overall effort was about 10-15 minutes. Really secure and won't interfere with my pedaling.The features of this bag are amazing. I love the fact you can access the 2 compartments from either side. Yes, the compartments are separated and the left side is much larger than the right. Normally when dealing with an issue on the road I end up having to empty my entire bag to get at what I want. This bag is so well organized I'll be able to easily get whatever it is I'm after without having to dump everything. Another advantage of this bag is there are numerous webbed compartments on the smaller side allowing me to organize all the little things (tire irons, battery, chain master link, quarter, valve core removal tools....) without fear of losing them. You'll note in my pictures I'm using the webbed bag on the large side to store a spare tube.If I notice any issues on the road I'll be back to update this review. I'm particularly interested in how well the mud flap keeps my posterior dry. My view right now is this is light years ahead of my old (name brand 'T') bag. I'm really happy and looking forward to riding with it.

Very useful design.