diff --git a/tests/test_plot/test_gerber.py b/tests/test_plot/test_gerber.py
index 2853ce12..e3f17197 100644
--- a/tests/test_plot/test_gerber.py
+++ b/tests/test_plot/test_gerber.py
@@ -40,6 +40,37 @@ ALL_LAYERS = ['B_Adhes',
               'F_SilkS',
               'Margin',
               ]
+ALL_EXTS = ['gba',
+            'gbr',
+            'gbl',
+            'gbr',
+            'gbs',
+            'gbp',
+            'gbo',
+            'gbr',
+            'gbr',
+            'gbr',
+            'gbr',
+            'gm1',
+            'gta',
+            'gbr',
+            'gtl',
+            'gbr',
+            'gts',
+            'gtp',
+            'gto',
+            'gbr',
+            ]
+INNER_LAYERS = ['GND_Cu',
+                'Power_Cu',
+                'Signal1_Cu',
+                'Signal2_Cu',
+                ]
+INNER_EXTS = ['g2',
+              'g5',
+              'g3',
+              'g4',
+              ]
 
 
 def test_gerber_2layer():
@@ -116,3 +147,34 @@ def test_gerber_variant_1():
     check_layers_exist(ctx, 'test', prj, ALL_LAYERS, '_(test)')
     check_components(ctx, 'test', prj, ['F_Paste', 'F_Adhes'], '_(test)', ['R2'], ['C1', 'R1', 'R3', 'C2'])
     ctx.clean_up(keep_project=True)
+
+
+def test_gerber_protel_1():
+    prj = 'good-project'
+    ctx = context.TestContext('test_gerber_protel_1', prj, 'gerber_inner_protel_1', GERBER_DIR)
+    ctx.run()
+    exts = ALL_EXTS+INNER_EXTS
+    for n, suf in enumerate(ALL_LAYERS+INNER_LAYERS):
+        ctx.expect_out_file(os.path.join(GERBER_DIR, prj+'_'+suf+'.'+exts[n]))
+    ctx.clean_up()
+
+
+def test_gerber_protel_2():
+    prj = 'good-project'
+    ctx = context.TestContext('test_gerber_protel_2', prj, 'gerber_inner_protel_2', GERBER_DIR)
+    ctx.run()
+    inner = ['gin'+str(int(layer[-1])-1) for layer in INNER_EXTS]
+    exts = ALL_EXTS+inner
+    files = []
+    for n, suf in enumerate(ALL_LAYERS+INNER_LAYERS):
+        ext = exts[n]
+        if ext == 'gm1':
+            ext = 'e_cut'
+        file = os.path.join(GERBER_DIR, prj+'_'+suf+'.'+ext.upper())
+        ctx.expect_out_file(file)
+        files.append(file)
+    assert ctx.search_err('Layer "Inner layer 6" isn\'t used')
+    ctx.search_in_file(os.path.join(GERBER_DIR, 'Report.txt'),
+                       ['Top layer: good-project_F_Cu.GTL', 'Basename: good-project'])
+    ctx.test_compress(prj+'-result.tar.gz', files)
+    ctx.clean_up()
diff --git a/tests/yaml_samples/gerber_inner_protel_1.kibot.yaml b/tests/yaml_samples/gerber_inner_protel_1.kibot.yaml
new file mode 100644
index 00000000..0ab03473
--- /dev/null
+++ b/tests/yaml_samples/gerber_inner_protel_1.kibot.yaml
@@ -0,0 +1,33 @@
+# Example KiBot config file for a basic 2-layer board
+kibot:
+  version: 1
+
+outputs:
+  - name: 'gerbers'
+    comment: "Gerbers for the Gerber god"
+    type: gerber
+    dir: gerberdir
+    options:
+      # generic layer options
+      exclude_edge_layer: false
+      exclude_pads_from_silkscreen: false
+      use_aux_axis_as_origin: false
+      plot_sheet_reference: false
+      plot_footprint_refs: true
+      plot_footprint_values: true
+      force_plot_invisible_refs_vals: false
+      tent_vias: true
+
+      # gerber options
+      line_width: 0.15
+      subtract_mask_from_silk: true
+      use_protel_extensions: true
+      gerber_precision: 4.6
+      create_gerber_job_file: false
+      gerber_job_file: 'test-%f.%x'
+      use_gerber_x2_attributes: true
+      use_gerber_net_attributes: false
+      output: '%f_%i.%x'
+
+    layers: all
+
diff --git a/tests/yaml_samples/gerber_inner_protel_2.kibot.yaml b/tests/yaml_samples/gerber_inner_protel_2.kibot.yaml
new file mode 100644
index 00000000..9454a68f
--- /dev/null
+++ b/tests/yaml_samples/gerber_inner_protel_2.kibot.yaml
@@ -0,0 +1,47 @@
+# Example KiBot config file for a basic 2-layer board
+kibot:
+  version: 1
+
+outputs:
+  - name: 'gerbers'
+    comment: "Gerbers for the Gerber god"
+    type: gerber
+    dir: gerberdir
+    options:
+      # generic layer options
+      exclude_edge_layer: false
+      exclude_pads_from_silkscreen: false
+      use_aux_axis_as_origin: false
+      plot_sheet_reference: false
+      plot_footprint_refs: true
+      plot_footprint_values: true
+      force_plot_invisible_refs_vals: false
+      tent_vias: true
+      # gerber options
+      line_width: 0.15
+      subtract_mask_from_silk: true
+      use_protel_extensions: true
+      gerber_precision: 4.6
+      create_gerber_job_file: false
+      gerber_job_file: 'test-%f.%x'
+      use_gerber_x2_attributes: true
+      use_gerber_net_attributes: false
+      output: '%f_%i.%x'
+      inner_extension_pattern: '.gin%n'
+      edge_cut_extension: '.e_cut'
+      uppercase_extensions: true
+      custom_reports:
+        - output: 'Report.txt'
+          content: 'Top layer: ${filename(F.Cu)}\nBasename: ${basename}\n'
+
+    layers: [all, In6.Cu]
+
+  - name: result
+    comment: Test tarball compress
+    type: compress
+    options:
+      format: TAR
+      compression: deflated
+      files:
+        - from_output: gerbers
+