SW-2895 - ESAW Reflection of Sound Apparatus 

For proving that angles of incidence and reflection are equal for any setting. A protector (actual 'D') is screen printed on a superior quality laminated board. It consists of two independent arms containing 12” long stainless steel pipes. One arm is set at any arbitrary angle and the other is adjusted ll one listens to the maximum sound. At the position of maximum sound to angles will be equal as indicated by the 'D' reading.