Mul T Lock Garrison threaded mortice cylinders are used on metal doors, mostly found on commercial buildings.
They are available as a matched pair keyed alike, we can also key them alike to the entire range of Garrison cylinders - and they can also be master keyed, call us for master keying pricing & options.
If you are looking for standard rim cylinders for nightlatches the Garrison version is here http://www.lockandkey.co.uk/products/Mul-T-Lock-Garrison-Rim-Cylinders-Garrison-Brass-Rim-Cylinder-32061.aspx