diff --git a/lib/Slic3r.pm b/lib/Slic3r.pm
index 5bf8bb306..38084eaf6 100644
--- a/lib/Slic3r.pm
+++ b/lib/Slic3r.pm
@@ -132,7 +132,7 @@ our $support_material_threshold = 45;
 our $support_material_pattern = 'rectilinear';
 our $support_material_spacing = 2.5;
 our $support_material_angle = 0;
-our $support_material_tool = 0;
+our $support_material_extruder = 0;
 our $start_gcode = "G28 ; home all axes";
 our $end_gcode = <<"END";
 M104 S0 ; turn off temperature
diff --git a/lib/Slic3r/Config.pm b/lib/Slic3r/Config.pm
index cd82a5eed..417dbc59c 100644
--- a/lib/Slic3r/Config.pm
+++ b/lib/Slic3r/Config.pm
@@ -320,12 +320,11 @@ our $Options = {
         cli     => 'support-material-angle=i',
         type    => 'i',
     },
-    'support_material_tool' => {
+    'support_material_extruder' => {
         label   => 'Extruder',
-        cli     => 'support-material-tool=i',
-        type    => 'select',
-        values  => [0,1],
-        labels  => [qw(Primary Secondary)],
+        cli     => 'support-material-extruder=i',
+        type    => 'i',
+        aliases => [qw(support_material_tool)],
     },
     'start_gcode' => {
         label   => 'Start G-code',
diff --git a/lib/Slic3r/GUI/SkeinPanel.pm b/lib/Slic3r/GUI/SkeinPanel.pm
index 77bbfc84f..7e57f6760 100644
--- a/lib/Slic3r/GUI/SkeinPanel.pm
+++ b/lib/Slic3r/GUI/SkeinPanel.pm
@@ -87,7 +87,7 @@ sub new {
         },
         support_material => {
             title => 'Support material',
-            options => [qw(support_material support_material_threshold support_material_pattern support_material_spacing support_material_angle support_material_tool)],
+            options => [qw(support_material support_material_threshold support_material_pattern support_material_spacing support_material_angle support_material_extruder)],
         },
     );
     $self->{panels} = \%panels;
diff --git a/lib/Slic3r/Print.pm b/lib/Slic3r/Print.pm
index ecf811d8d..5a2fb98e4 100644
--- a/lib/Slic3r/Print.pm
+++ b/lib/Slic3r/Print.pm
@@ -510,7 +510,7 @@ sub write_gcode {
     my $gcodegen = Slic3r::GCode->new;
     my $min_print_speed = 60 * $Slic3r::min_print_speed;
     my $dec = $gcodegen->dec;
-    if ($Slic3r::support_material && $Slic3r::support_material_tool > 0) {
+    if ($Slic3r::support_material && $Slic3r::support_material_extruder > 0) {
         print $fh $gcodegen->set_tool(0);
     }
     print $fh $gcodegen->set_fan(0, 1) if $Slic3r::cooling && $Slic3r::disable_fan_first_layers;
@@ -601,12 +601,12 @@ sub write_gcode {
             
             # extrude support material
             if ($layer->support_fills) {
-                $gcode .= $gcodegen->set_tool($Slic3r::support_material_tool)
-                    if $Slic3r::support_material_tool > 0;
+                $gcode .= $gcodegen->set_tool($Slic3r::support_material_extruder)
+                    if $Slic3r::support_material_extruder > 0;
                 $gcode .= $gcodegen->extrude_path($_, 'support material') 
                     for $layer->support_fills->shortest_path($gcodegen->last_pos);
                 $gcode .= $gcodegen->set_tool(0)
-                    if $Slic3r::support_material_tool > 0;
+                    if $Slic3r::support_material_extruder > 0;
             }
         }
         return if !$gcode;