http://twocitiestwowheels.blogspot.com/2007/03/zwei-drei-geschwindigkeiten.html
Scroll down and you'll see a bit about a similar lock. From a time and place where you didn't have to be so secure so largely useless today i'd say.
@M_V started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
http://twocitiestwowheels.blogspot.com/2007/03/zwei-drei-geschwindigkeiten.html
Scroll down and you'll see a bit about a similar lock.
From a time and place where you didn't have to be so secure so largely useless today i'd say.