This was a risky job drilling only millimeters from the glass of a 1960s glass panel door. This was one to really take my time with, I used a jig and high speed drill to cut down on vibrations and not risk cracking the glass. But in the end all was well and the customer was very happy. If you need to add extra locks to your doors or you have just moved into a new home then give me a call on 07769312235. I cover Letchworth and all the connecting areas.