The PVX-4130 high-voltage pulser ships with a checkout sheet that documents functional verification testing performed before delivery. A formal calibration certificate with traceable measurements is included with every calibration service return, and can also be requested at the time of new unit purchase at no additional charge. Berkeley Nucleonics recommends annual calibration for PVX units in active use. To request a calibration certificate with your new PVX-4130 order, include the request at the time of purchase.