When the mower arrived it started with difficulty, ran roughly, and after about 30 minutes use stopped working altogether. I noticed a small spring had become detached near the filter. I took the mower to a local Hayter agent who was easily able to replace the spring, which was faulty, and the mower is now fine. The agent explained that suppliers such as GM (through Amazon) and B&Q don't run the mower before delivery, they just put them in the box, and so do not detect small problems such as this.