The Ultrasonic Cleaner produced amazing results the first time I used it, cleaning two old rifle receivers of crud I did not even know existed! The unit appears to be limited to a 30 minute cycle which is OK, but my I got better results with a second cycle, and will probably give them a third cycle still. Keeping in mind that some of the crud may have been over 100 years old. You need to be careful with the lid, as it is very thin material and may be damaged if dropped, which is why I only gave a 4-star for quality. Everything else was very well built.