Hi LEGO Ideas! I have been working on this padlock and key model on-and-off for more than a year. It was inspired by one of my favourite YouTubers.
I believe this is the world's first working LEGO pin tumbler lock. I went through dozens of design iterations to get the mechanism working smoothly and reliably, and making the model strong enough to withstand significant forces. It was a big challenge to pack it all into a roughly 8 x 16 footprint and relatively small piece count (~700). Balancing all of the competing design constraints on this model felt a bit like playing a Zachtronics game. I hope that the low-ish piece count means it could be released at a more affordable price point than most recent Ideas sets.
It comes with a pick, torque wrench and shim, which can be used to try and open the lock without using the key. The panels on the front and back come off easily, and the back parts of the body are transparent, so you can watch exactly what's going on inside as you try and pick it. Once you get good enough, you can try doing it with the panels back on!
It's possible to customise your padlock by building one of 20+ different key designs (and the corresponding pins), so that your friends' keys won't work on your lock.
The build style of this set is inspired by my two favourite Ideas sets; the Pop-up Book, and the Typewriter - they pack in Technic-style functionality, but they still feel like normal LEGO System models. I deliberately left lots of lovely studs showing and I'm particularly pleased with how chunky and solid the key feels, as well as the satisfying sounds the lock makes when you open and close it.