I have just wasted half hour watching several YouTube videos of people opening D locks and other locks with a tubular key with a ball point pen case. Seeing how many people use these locks I find this a little alarming and looked to see if Kryptonite and other makers had addressed the problem. I couldn't find any info at all. Most of the videos were several years old so I am wondering if the locks have had any modifications to keep them as safe as possible. None of my bike locks have this type of key, but my car steering wheel lock, the type that is a bar which threads through the steering wheel, does so perhaps I will try it out later!