Ullswater :

a classic messenger bag with a strap that can attach to your suitcase-a useful travel companion. 

Strong 5cm wide canvas shoulder strap adjusts in length from 61cm to 112cm). Rear carry handle fits across a suitcase arm. Stylish and practical front flap with magnetic closer. Envelope sides to prevent weather (or light fingers) getting into your bag. Full width brass zipped rear pocket. Inside: leather envelope style brass zipped pocket and brass key hook. Padded section to protect your laptop. 28cm x 10cm. 33cm high
Currently available: Tiberthwaite  Tweed & Smit Mark