Arundel's 'The Dual' seat bag is so called as it's designed to carry two of each essential, two innertubes, two CO2 cartridges and the inflater. It's a tight fit but it all fits none the less. My preferred selection was one tube, CO2 inflator and canister plus a small multi tool.
Using a drybag as a lightweight saddlebag is the topic of the latest post on the audaxing blog
In a sense there is no point in doing this for weight saving (even though it saves a whole kilo) as the bag will contain lots of heavy stuff. Also it's nothing compared to the vast bulk of the person on the bike
Anyway, drybags are great and worth considering for bike luggage
If you have a Carradice saddlebag then the chances are you'll already have a Bagman, or one of the assorted variants. Although Carradice bags are a joy and wonder, they can be a bit of a sod to fit to your bike. Unless you are tall enough to have enough space between saddle and rear wheel you'll end up with a saddlebag dragging on your back wheel, which is just rubbish.
Avenir's 1.5 litre Sonic Welded Waterproof Seat Pack represents excellent value. The top-notch 840/420 denier laminated polyurethane construction comes complete with welded seams and the roll top closure gobbles multi tools, a long handled fixie-type wrench, spare tubes, race-cape, energy bars, keys, wallet, smart phone, energy bars and contingency lighting. The prodigious outer flap not only locks the great British weather out but also incorporates a blinky mount for neat, nocturnal safety.
Way back in the mists of time, I tested the Carradice Super C saddlebag. I fell in love with its simplicity, convenience and retro-styling and it has been strapped to my bike ever since. What I didn't fully appreciate is that the Super C is in effect the modern version of the Nelson, which is what I'm testing here.
Cyclodelic aim to bring a little girlie style back into cycling kit, and the Saddle Bag shows just how committed to this end they are.
Where most seatpacks are fabric-based affairs, the Ortlief Mudracer has a thermoformed semi-hard shell to keep out the elements. If you've got stuff you need to take on a ride, and you need to keep it dry this is the seatpack for you.
The Mudpack's weather protection starts with a full zip protected by a silicon rubber flap which pulls down to keep water and debris out. Inside there's a zippered pocket at the top that's just big enough for a phone, and a soft padded main compartment that'll swallow a spare tube, a basic toolkit and some energy bars.