diff --git a/python/plugins/processing/algs/qgis/FixedDistanceBuffer.py b/python/plugins/processing/algs/qgis/FixedDistanceBuffer.py
index c782ae31c71..45e385cb017 100644
--- a/python/plugins/processing/algs/qgis/FixedDistanceBuffer.py
+++ b/python/plugins/processing/algs/qgis/FixedDistanceBuffer.py
@@ -70,9 +70,11 @@ class FixedDistanceBuffer(QgisAlgorithm):
                                                               self.tr('Input layer')))
 
         self.addParameter(QgsProcessingParameterNumber(self.DISTANCE,
-                                                       self.tr('Distance'), defaultValue=10.0))
+                                                       self.tr('Distance'), type=QgsProcessingParameterNumber.Double,
+                                                       defaultValue=10.0))
         self.addParameter(QgsProcessingParameterNumber(self.SEGMENTS,
-                                                       self.tr('Segments'), type=QgsProcessingParameterNumber.Integer, minValue=1, defaultValue=5))
+                                                       self.tr('Segments'), type=QgsProcessingParameterNumber.Integer,
+                                                       minValue=1, defaultValue=5))
         self.addParameter(QgsProcessingParameterBoolean(self.DISSOLVE,
                                                         self.tr('Dissolve result'), defaultValue=False))
         self.end_cap_styles = [self.tr('Round'),
@@ -90,7 +92,8 @@ class FixedDistanceBuffer(QgisAlgorithm):
             self.tr('Join style'),
             options=self.join_styles, defaultValue=0))
         self.addParameter(QgsProcessingParameterNumber(self.MITER_LIMIT,
-                                                       self.tr('Miter limit'), minValue=0, defaultValue=2))
+                                                       self.tr('Miter limit'), type=QgsProcessingParameterNumber.Double,
+                                                       minValue=0, defaultValue=2))
 
         self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Buffer'), QgsProcessing.TypeVectorPolygon))
 
diff --git a/python/plugins/processing/algs/qgis/SingleSidedBuffer.py b/python/plugins/processing/algs/qgis/SingleSidedBuffer.py
index abff1690ce5..4b12a0adb79 100644
--- a/python/plugins/processing/algs/qgis/SingleSidedBuffer.py
+++ b/python/plugins/processing/algs/qgis/SingleSidedBuffer.py
@@ -60,7 +60,8 @@ class SingleSidedBuffer(QgisFeatureBasedAlgorithm):
 
     def initParameters(self, config=None):
         self.addParameter(QgsProcessingParameterNumber(self.DISTANCE,
-                                                       self.tr('Distance'), defaultValue=10.0))
+                                                       self.tr('Distance'), QgsProcessingParameterNumber.Double,
+                                                       defaultValue=10.0))
         self.addParameter(QgsProcessingParameterEnum(
             self.SIDE,
             self.tr('Side'),
@@ -75,7 +76,8 @@ class SingleSidedBuffer(QgisFeatureBasedAlgorithm):
             self.tr('Join style'),
             options=self.join_styles))
         self.addParameter(QgsProcessingParameterNumber(self.MITER_LIMIT,
-                                                       self.tr('Miter limit'), minValue=1, defaultValue=2))
+                                                       self.tr('Miter limit'), QgsProcessingParameterNumber.Double,
+                                                       minValue=1, defaultValue=2))
 
     def name(self):
         return 'singlesidedbuffer'
@@ -84,7 +86,7 @@ class SingleSidedBuffer(QgisFeatureBasedAlgorithm):
         return self.tr('Single sided buffer')
 
     def outputName(self):
-        return self.tr('Buffers')
+        return self.tr('Buffer')
 
     def inputLayerTypes(self):
         return [QgsProcessing.TypeVectorLine]
diff --git a/python/plugins/processing/algs/qgis/VariableDistanceBuffer.py b/python/plugins/processing/algs/qgis/VariableDistanceBuffer.py
index aa888e98ffc..4fff0e0fdaf 100644
--- a/python/plugins/processing/algs/qgis/VariableDistanceBuffer.py
+++ b/python/plugins/processing/algs/qgis/VariableDistanceBuffer.py
@@ -90,7 +90,8 @@ class VariableDistanceBuffer(QgisAlgorithm):
             self.tr('Join style'),
             options=self.join_styles, defaultValue=0))
         self.addParameter(QgsProcessingParameterNumber(self.MITER_LIMIT,
-                                                       self.tr('Miter limit'), minValue=0, defaultValue=2))
+                                                       self.tr('Miter limit'), type=QgsProcessingParameterNumber.Double,
+                                                       minValue=0, defaultValue=2))
 
         self.addParameter(
             QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Buffer'), QgsProcessing.TypeVectorPolygon))