diff --git a/magneticfield/inc/fieldPropagatorConstBz.h b/magneticfield/inc/fieldPropagatorConstBz.h
index b2d88325..0f7401a7 100644
--- a/magneticfield/inc/fieldPropagatorConstBz.h
+++ b/magneticfield/inc/fieldPropagatorConstBz.h
@@ -81,7 +81,7 @@ __host__ __device__ double fieldPropagatorConstBz::ComputeStepAndNextVolume(
   double momentumXYMag =
       momentumMag * sqrt((1. - direction[2]) * (1. + direction[2])); // only XY component matters for the curvature
 
-  double curv = std::fabs(ConstBzFieldStepper::kB2C * charge * BzValue) / (momentumXYMag + 1.0e-30); // norm for step
+  double curv = std::fabs(fieldConstants::kB2C * charge * BzValue) / (momentumXYMag + 1.0e-30); // norm for step
 
   constexpr double gEpsilonDeflect = 1.E-2 * copcore::units::cm;