diff --git a/gstlal-inspiral/bin/gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs b/gstlal-inspiral/bin/gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs
index e94d8d5b14213e231e67d8c0752c5e3d5261273c..228e1ef9b5577f9117c37547609c8457a90ab546 100755
--- a/gstlal-inspiral/bin/gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs
+++ b/gstlal-inspiral/bin/gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs
@@ -29,7 +29,7 @@ options = parser.parse_args()
 
 if options.start is not None and options.stop is not None:
 	if options.start % inspiral_extrinsics.TimePhaseSNR.numchunks or options.stop % inspiral_extrinsics.TimePhaseSNR.numchunks:
-		raise ValueError("start and stop must be multiple of %d" % TimePhaseSNR.numchunks)
+		raise ValueError("start and stop must be multiple of %d" % inspiral_extrinsics.TimePhaseSNR.numchunks)
 	IE = inspiral_extrinsics.TimePhaseSNR.from_hdf5(fname = options.cov_mat_h5, verbose = True, margstart = options.start, margstop = options.stop)
 else:
 	IE = inspiral_extrinsics.TimePhaseSNR.from_hdf5(fname = options.cov_mat_h5, verbose = True)