Diaphragm Pumps are available in various materials.

Granzow, Inc. Mar 05, 2002

Press Release Summary:

Non-metallic pumps are machined from solid blocks of PP and PTFE to ensure stability of shape, with less stress on body.
Polished stainless-steel pumps are USDA approved and manufactured to 3-A standards. Aluminum, PP, PTFE, and sanitary pumps are available in 5 sizes from 1/2 to 3 in.

Original Press Release:

Granzow, Inc., Is Introducing A New Family Of Air Operated Diaphragm Pumps In Polished Stainless Steel, PTFE, PP and Aluminum

The non-metallic pumps are machined from solid blocks of PP and PTFE to ensure the highest possible stability of shape with less stress on the body.

The polished stainless steel pumps are USDA approved and also manufactures to 3-A standards.

The range of aluminum, PP, PTFE and sanitary pumps are available in five different sizes from 1/2" to 3".