<html> <head> <style> .hmmessage P { margin:0px; padding:0px } body.hmmessage { FONT-SIZE: 10pt; FONT-FAMILY:Tahoma } </style> </head> <body class='hmmessage'><div style="text-align: left;">I had created and manufactured a product (liquid formula) specifically for cleaning brass musical instruments. I have been selling it for many years to schools and band instrument repair technicians. During my trial testing I looked at Simple Green and their formulation variables. At that time Simple Green did not pass mil spec for brass. There also was an issue with aluminum. Since I was concerned as to the long term affects on musical instrument being cleaned by the general population, my chemical engineer and I concluded that our formulation was a better way to go since it was specifically for brass. That being said, here's a letter(edited) I received directly from their Reg. Coordinator. Conclude what you wish, but I wouldn't risk using the product on a piano plate which will be subject to constant (and variable) pressures. My 2c Gerry Cousins Dear Gerry: Thanks for your inquiry, and for being such a long-term supporter of Simple Green! The information you've heard comes from the military.�* They put cleaning products through a rigorous "mil-prf" testing before allowing use on aircraft.�* The hydrogen embrittlement test involves soaking a coupon of cadmium and brass plated AISI 4340 steel in full-strength and 10% solution and then subjecting the coupons to tensile strength (stretching) for 150 hours.�* Failures prior to 150 hours produce a failure of the cleaner to pass mil-prf.�* ASTM stipulates that this test is only applicable to the specified steel and brass and results cannot be extrapolated to any other kind of metal.�* Simple Green did not pass this test and, therefore, has not been marketed to the aircraft industry. Thanks again for contacting us, and for choosing Simple Green! Sincerely, Carol Chapin Environmental & Regulatory Coordinator SIMPLE GREEN (800) 228-0709 cchapin@simplegreen.com </div></body> </html>