I have a Sparrows Master Switch and am having trouble using it on a Master No.3 padlock. I can't seem to locate the slot at the back of the lock, where the talon mentioned in the sparrows video, fits into.
My padlock is brand new and I noticed that the shackle is retained by ball bearings. Whereas, the older version of the No.3 does not have the semicircular shackle retaining grooves, the retaining grooves are squared.
I'm wondering if they "improved" the design and the changes prevent me from using the Switch on this model of the No.3?