diff --git a/src/driver_sharky.cc b/src/driver_sharky.cc
index 5c40ca1..dd54fe0 100644
--- a/src/driver_sharky.cc
+++ b/src/driver_sharky.cc
@@ -79,13 +79,11 @@ MeterSharky::MeterSharky(MeterInfo &mi, DriverInfo &di) : MeterCommonImplementat
     addNumericFieldWithExtractor(
         "total_volume",
         Quantity::Volume,
-        NoDifVifKey,
         VifScaling::Auto,
-        MeasurementType::Instantaneous,
-        VIFRange::Volume,
-        StorageNr(0),
-        TariffNr(0),
-        IndexNr(1),
+        FieldMatcher::build()
+            .set(MeasurementType::Instantaneous)
+            .set(VIFRange::Volume)
+        ,
         PrintProperty::JSON | PrintProperty::FIELD,
         "The total heating media volume recorded by this meter.",
         SET_FUNC(total_volume_m3_, Unit::M3),
diff --git a/src/dvparser.h b/src/dvparser.h
index d3697a1..c83083c 100644
--- a/src/dvparser.h
+++ b/src/dvparser.h
@@ -201,18 +201,18 @@ struct FieldMatcher
     bool match_vif_range = false;
     VIFRange vif_range { VIFRange::Any };
 
-    // Match the storage nr.
-    bool match_storage_nr = false;
+    // Match the storage nr. If no storage is specified, default to match only 0.
+    bool match_storage_nr = true;
     StorageNr storage_nr_from { 0 };
     StorageNr storage_nr_to { 0 };
 
-    // Match the tariff nr.
-    bool match_tariff_nr = false;
+    // Match the tariff nr. If no tariff is specified, default to match only 0.
+    bool match_tariff_nr = true;
     TariffNr tariff_nr_from { 0 };
     TariffNr tariff_nr_to { 0 };
 
-    // Match the subunit.
-    bool match_subunit_nr = false;
+    // Match the subunit. If no subunit is specified, default to match only 0.
+    bool match_subunit_nr = true;
     SubUnitNr subunit_nr_from { 0 };
     SubUnitNr subunit_nr_to { 0 };
 
diff --git a/src/meters.cc b/src/meters.cc
index fcd6a42..899035b 100644
--- a/src/meters.cc
+++ b/src/meters.cc
@@ -872,6 +872,37 @@ void MeterCommonImplementation::addNumericFieldWithExtractor(
             ));
 }
 
+void MeterCommonImplementation::addNumericFieldWithExtractor(
+    string vname,
+    Quantity vquantity,
+    VifScaling vif_scaling,
+    FieldMatcher matcher,
+    PrintProperties print_properties,
+    string help,
+    function<void(Unit,double)> setValueFunc,
+    function<double(Unit)> getValueFunc)
+{
+    string default_unit = unitToStringLowerCase(defaultUnitForQuantity(vquantity));
+    string field_name = vname+"_"+default_unit;
+    fields_.push_back(field_name);
+
+    prints_.push_back(
+        FieldInfo(vname,
+                  vquantity,
+                  defaultUnitForQuantity(vquantity),
+                  vif_scaling,
+                  matcher,
+                  help,
+                  print_properties,
+                  field_name,
+                  getValueFunc,
+                  NULL,
+                  setValueFunc,
+                  NULL,
+                  NoLookup
+            ));
+}
+
 void MeterCommonImplementation::addNumericField(
     string vname,
     Quantity vquantity,
diff --git a/src/meters_common_implementation.h b/src/meters_common_implementation.h
index 0843bec..f3b09d7 100644
--- a/src/meters_common_implementation.h
+++ b/src/meters_common_implementation.h
@@ -109,6 +109,16 @@ protected:
         function<void(Unit,double)> setValueFunc, // Use the SET macro above.
         function<double(Unit)> getValueFunc); // Use the GET macro above.
 
+    void addNumericFieldWithExtractor(
+        string vname,          // Name of value without unit, eg total
+        Quantity vquantity,    // Value belongs to this quantity.
+        VifScaling vif_scaling,
+        FieldMatcher matcher,
+        PrintProperties print_properties, // Should this be printed by default in fields,json and hr.
+        string help,
+        function<void(Unit,double)> setValueFunc, // Use the SET macro above.
+        function<double(Unit)> getValueFunc); // Use the GET macro above.
+
     void addNumericField(
         string vname,          // Name of value without unit, eg total
         Quantity vquantity,    // Value belongs to this quantity.