The Dytran model 3038A is a back–to back calibration accelerometer designed to mount on a miniature dynamic shaker and is used to calibrate other (TEST) accelerometers which are attached to its upper mounting surface. It offers a convenient means of determining the sensitivity and frequency response characteristics of unknown acceleration, velocity, and displacement sensors. A vibration laboratory already equipped with an electrodynamic shaker and control system can easily incorporate use of the series 3027 to accomplish in–house NIST traceable calibrations. Model 3038A offers 10 mV/g sensitivity, and mounts to a shaker head via a 10–32 tapped hole.