diff --git a/src/hisp/festim_models/mb_model.py b/src/hisp/festim_models/mb_model.py
index 5887b1d..800bfa4 100644
--- a/src/hisp/festim_models/mb_model.py
+++ b/src/hisp/festim_models/mb_model.py
@@ -318,8 +318,9 @@ def make_B_mb_model(
 
     vertices = np.concatenate(  # 1D mesh with extra refinement
         [
-            np.linspace(0, 30e-9, num=200),
-            np.linspace(30e-9, L, num=200),
+            np.linspace(0, 5e-9, num=300),
+            np.linspace(5e-9, 1e-8, num=500),
+            np.linspace(1e-8, L, num=300),
         ]
     )
     my_model.mesh = F.Mesh1D(vertices)
@@ -540,7 +541,7 @@ def make_B_mb_model(
     ############# Settings #############
     my_model.settings = F.Settings(
         atol=1e10,
-        rtol=1e-10,
+        rtol=1e-5,
         max_iterations=1000,
         final_time=final_time,
     )