The Betts spacers and adapters are available in various styles. The bolt patterns are in accordance with TTMA recommended practices. Steel and stainless adapters are rated for a MAWP of 75 psi [5.2 bar] and aluminum adapters are rated for a MAWP of 50 psi [3.4 bar]. For single spacer adapter see piping weld flanges Section 40 Page 2B. All material options may not be available in all sizes and versions.