Compass Minerals International, Inc. is a producer of essential minerals, including salt, sulfate of potash (SOP) specialty fertilizer and magnesium chloride. It is also working to develop a long-term fire-retardant business. Its segments include Salt and Plant Nutrition. Salt segment provides highway deicing salt to customers in North America and the United Kingdom, as well as consumer deicing and water conditioning products, ingredients used in consumer and commercial food preparation, and other salt-based products for consumer, industrial, chemical and agricultural applications in North America. In the United Kingdom, it operates a records management business utilizing excavated areas of its Winsford salt mine with one other location in London, England. Plant Nutrition segment produces and markets SOP products in various grades worldwide to distributors and retailers of crop inputs, as well as growers and for industrial uses. It markets is SOP under the trade name Protassium+.