The G.R.A.S. RA0090 is a larger-volume coupler for enabling G.R.A.S. 42AA/AD Pistonphone to produce a sound pressure level of 94 dB instead of 114 dB re. 20μPa. Essential when calibrating highly sensitive, G.R.A.S. low noise measuring systems.
Quality & Warranty
G.R.A.S. accessories are made of stainless steel, alloys and high-quality composites. These items are covered by a 2 year warranty respecting their intended use.
On consumables like batteries, cables and windscreen we offer a 6 month warranty.