These irradiated fused quartz rods are useful for monitoring performance of pulsed EPR spectrometers, both as a function of time to ensure continued good performance, and for interlaboratory comparisons. The 100 mm long, 4 mm O.D. fused quartz rods were irradiated by NIST to a dose of 261 Gy with 60Co gamma.  Defect levels were chosen to give X-band S/N in a useful range for single spin echoes. The dimensions are selected to fit Bruker FlexLine X-band EPR resonators, but they can be used with other resonators for quality tests.