diff --git a/lib/src/model/flutter_slider_tooltip.dart b/lib/src/model/flutter_slider_tooltip.dart
index 66172c0..f6c775b 100644
--- a/lib/src/model/flutter_slider_tooltip.dart
+++ b/lib/src/model/flutter_slider_tooltip.dart
@@ -2,7 +2,7 @@ import 'package:flutter/widgets.dart';
 import 'package:flutter_xlider/flutter_xlider.dart';
 
 class FlutterSliderTooltip {
-  Widget Function(dynamic value)? custom;
+  Widget Function(dynamic value, String? side)? custom;
   String Function(String value)? format;
   TextStyle? textStyle;
   FlutterSliderTooltipBox? boxStyle;
diff --git a/lib/src/view/flutter_slider_widget.dart b/lib/src/view/flutter_slider_widget.dart
index 0d97dd9..d8fa480 100644
--- a/lib/src/view/flutter_slider_widget.dart
+++ b/lib/src/view/flutter_slider_widget.dart
@@ -2000,7 +2000,7 @@ class _FlutterSliderState extends State<FlutterSlider>
           key: (side == 'left') ? leftTooltipKey : rightTooltipKey,
 //            alignment: Alignment.center,
           child: (widget.tooltip != null && widget.tooltip!.custom != null)
-              ? widget.tooltip!.custom!(value)
+              ? widget.tooltip!.custom!(value, side)
               : Container(
                   padding: EdgeInsets.all(8),
                   decoration: _tooltipData.boxStyle!.decoration,