We've had one of these backpacks on test over the past few weeks and it has performed extremely well keeping our kit dry. We give it a 9.5/10 

The backpack is ideal for your daily commute. It has one large main pocket that will take an average size laptop a front pocket for niknaks. The approx volume is 15ltrs.

Importantly for a motorcyclist, it as water resistant as it can be, has a waist and chest strap to make sure it stays in place securely. The waist strap has a couple of small zipped pockets for keys, coins etc. There's also a carry handle fixed to the top of the bag.

The bag is ultra lightweight at only 0.65kgs. The dimensions are 23X13X40 CM