I've had this for a long time. Base: 28cm x 14cm, Height: 37cm You can reach into the bag from the side while wearing it. Inside, there's one zippered pocket, about 20cm x 15cm. There are also two pockets, about 20cm x 12cm each. There are also pockets on both sides, under the armpits, about 20cm x 12cm each, as shown in the second photo. The flap also has a zippered pocket.