Literature from PEM Fastening Systems details its line of self - clinching fasteners for use in stainless steel sheets. The company's Type SP nuts are made from precipitation-hardened stainless steel, appropriate for sheet hardness up to Rockwell B 90. Types FH4, SO4, BSO4, and PFC4 fasteners are made from 400 Series stainless steel, appropriate for sheet hardness up to Rockwell B88 (92 for Type FH4). According to the brochure, these fasteners are used extensively in medical, food, fluid handling, outdoor, and other similar types of equipment.
PEM Fastening Systems