Complaining about a rack shelf

I had not had any problems with the rack shelf before the incident. It actually seemed to be quite durable so I thought it would survive for years. I read all the instructions carefully and did not exceed the weight limit suggested by the manufacturer. My equipment was not that heavy, anyway, so I did not expect the shelf to break. But it did one day. I was sitting in the office, making some calculations, when I suddenly heard a dull sound. The door to the server room is soundproof but if something is loud enough, you can hear the sound anyway. ^That must be something serious^, I though, and I rushed to the room to check what was going on. When I opened the door, one of the computers, the biggest one, was hanging somewhere between the second and the third levels of the rack shelf. Fortunately, it didn^t fall down to the floor. I came nearer and saw that two connections on the right were broken, and the screws were missing. I could not remember whether they had been there before, but I decided to call the shop I had bought the rack shelf at and complain abut the product. I was pleasantly surprised with the service. The man who answered the phone asked me to describe the situation in detail. Then he took my address and promised to send another shelf within a week. I did not have to cover any additional costs.