diff --git a/model/head/spherefacer.py b/model/head/spherefacer.py
index 2225a21..85db8d7 100644
--- a/model/head/spherefacer.py
+++ b/model/head/spherefacer.py
@@ -29,6 +29,7 @@ def get_d_theta(cos_theta, y, magn_type, m):
 
     return d_theta
 
+# Warning: Both SphereFaceR_N and SphereFaceR_S are needed to be tested before using.
 
 class SphereFaceR_N(nn.Module):
     """ reference: <SphereFace Revived: Unifying Hyperspherical Face Recognition>