One of San Gabriel, Calif.-based Rainshow’r Manufacturing’s ongoing product improvements is a solid brass collar molded into the body of the CQ-1000 shower filter inlet thereby strengthening the filter body, and making it impossible to crack the filter body by over-tightening during installation. This durable, American-made, brass collar is unique to the company’s shower filters. In addition to the brass collar, the CQ-1000 features O-ring seals and special washers to ensure against unwanted leaks.