diff --git a/lib/game/components/crossing_ramp.dart b/lib/game/components/crossing_ramp.dart
index 3b9b4c53..315318f0 100644
--- a/lib/game/components/crossing_ramp.dart
+++ b/lib/game/components/crossing_ramp.dart
@@ -3,13 +3,37 @@
 import 'package:flame_forge2d/flame_forge2d.dart';
 import 'package:pinball/game/game.dart';
 
-enum RampOrientation { up, down }
+/// Indicates a orientation of the ramp entrance/exit.
+///
+/// Used to know if ramps are looking up or down of the board.
+enum RampOrientation {
+  /// Looking up of the board.
+  up,
+
+  /// Looking up of the board.
+  down,
+}
+
+/// Indicates a type of the ramp.
+///
+/// Used to set the maskBits of the ramp to determine their possible collisions.
+enum RampType {
+  /// Collide with all elements.
+  all,
 
-enum RampType { all, jetpack, sparky }
+  /// Collide only with Jetpack group elements.
+  jetpack,
 
+  /// Collide only with Sparky group elements.
+  sparky,
+}
+
+/// Utility methods for [RampType].
 extension RampTypeX on RampType {
+  /// Mask of bits for each [RampType].
   int get maskBits => _getRampMaskBits(this);
 
+  /// Mask of bits for each [RampType].
   int _getRampMaskBits(RampType type) {
     switch (type) {
       case RampType.all:
@@ -22,17 +46,26 @@ extension RampTypeX on RampType {
   }
 }
 
+/// {@template ramp_area}
+/// [BodyComponent] located at the entrance and exit of a ramp.
+///
+/// Detects when a [Ball] goes through it,
+/// Collisions with [RampArea] are listened by [RampAreaCallback].
+/// {@endtemplate}
 abstract class RampArea extends BodyComponent {
   RampArea({
     required Vector2 position,
-    required int maskBits,
+    required int categoryBits,
   })  : _position = position,
-        _maskBits = maskBits;
+        _categoryBits = categoryBits {
+    // TODO(ruialonso): remove paint color for BodyComponent.
+    // Left white for dev and testing.
+  }
 
   final Vector2 _position;
-  final int _maskBits;
+  final int _categoryBits;
 
-  int get maskBits => _maskBits;
+  int get categoryBits => _categoryBits;
   Shape get shape;
   RampOrientation get orientation;
 
@@ -46,16 +79,21 @@ abstract class RampArea extends BodyComponent {
       ..type = BodyType.static;
 
     final body = world.createBody(bodyDef);
-    body.createFixture(fixtureDef).filterData
-      ..categoryBits = Filter().maskBits
-      ..maskBits = Filter().maskBits;
+    body.createFixture(fixtureDef).filterData.categoryBits = _categoryBits;
 
     return body;
   }
 }
 
+/// {@template ramp_area_callback}
+/// Listens when a [Ball] goes through a [RampArea] and gets into a [Pathway]
+/// ramp, in order to avoid collisions with other crossing ramps.
+/// Modifies [Ball]'s maskBits while is inside the ramp. When exits sets [Ball]
+/// maskBits to collide with all elements.
+/// {@endtemplate}
 abstract class RampAreaCallback<Area extends RampArea>
     extends ContactCallback<Ball, Area> {
+  /// Collection of balls inside ramp pathway.
   Set get ballsInside;
 
   @override
@@ -66,7 +104,7 @@ abstract class RampAreaCallback<Area extends RampArea>
   ) {
     int maskBits;
     if (!ballsInside.contains(ball)) {
-      maskBits = area.maskBits;
+      maskBits = area.categoryBits;
       ballsInside.add(ball);
     } else {
       maskBits = RampType.all.maskBits;
diff --git a/lib/game/components/jetpack_ramp.dart b/lib/game/components/jetpack_ramp.dart
index d5b805f8..78102f8e 100644
--- a/lib/game/components/jetpack_ramp.dart
+++ b/lib/game/components/jetpack_ramp.dart
@@ -3,12 +3,25 @@ import 'package:flame/extensions.dart';
 import 'package:flame_forge2d/flame_forge2d.dart';
 import 'package:pinball/game/game.dart';
 
+/// {@template jetpack_ramp}
+/// Represent the upper left blue ramp for the game.
+///
+/// Group of [Component]s composed by a [Pathway.arc] as the ramp, and two
+/// [JetpackRampArea] at the entrance and exit of the ramp, to detect when
+/// a ball gets into/out of the ramp.
+/// {@endtemplate}
 class JetpackRamp extends PositionComponent with HasGameRef<PinballGame> {
   JetpackRamp({
     required Vector2 position,
   })  : _position = position,
         super();
 
+  final double _radius = 200;
+  final double _width = 80;
+  final double _angle = radians(210);
+  final double _rotation = radians(-10);
+  final double _entranceRotation = radians(15);
+  final double _exitRotation = radians(-5);
   final Vector2 _position;
 
   @override
@@ -17,25 +30,25 @@ class JetpackRamp extends PositionComponent with HasGameRef<PinballGame> {
       Pathway.arc(
         color: const Color.fromARGB(255, 8, 218, 241),
         position: _position,
-        width: 80,
-        radius: 200,
-        angle: radians(210),
-        rotation: radians(-10),
-        maskBits: RampType.jetpack.maskBits,
+        width: _width,
+        radius: _radius,
+        angle: _angle,
+        rotation: _rotation,
+        categoryBits: RampType.jetpack.maskBits,
       ),
     );
 
     await add(
       JetpackRampArea(
         position: _position + Vector2(-10.5, 0),
-        rotation: radians(15),
+        rotation: _entranceRotation,
         orientation: RampOrientation.down,
       ),
     );
     await add(
       JetpackRampArea(
         position: _position + Vector2(20.5, 3),
-        rotation: radians(-5),
+        rotation: _exitRotation,
         orientation: RampOrientation.down,
       ),
     );
@@ -44,6 +57,12 @@ class JetpackRamp extends PositionComponent with HasGameRef<PinballGame> {
   }
 }
 
+/// {@template jetpack_ramp_area}
+/// Implementation of [RampArea] for sensors in [JetpackRamp].
+///
+/// [RampArea] with [RampType.jetpack] to filter [Ball]s collisions
+/// inside [JetpackRamp].
+/// {@endtemplate}
 class JetpackRampArea extends RampArea {
   JetpackRampArea({
     required Vector2 position,
@@ -53,11 +72,18 @@ class JetpackRampArea extends RampArea {
         _orientation = orientation,
         super(
           position: position,
-          maskBits: RampType.jetpack.maskBits,
+          categoryBits: RampType.jetpack.maskBits,
         );
 
+  /// Orientation of entrance/exit of [JetpackRamp] where
+  /// this [JetpackRampArea] is placed.
   final RampOrientation _orientation;
+
+  /// Rotation of the [RampArea] to place it right at the
+  /// entrance/exit of [JetpackRamp].
   final double _rotation;
+
+  /// Size of the [RampArea] placed at the entrance/exit of [JetpackRamp].
   final int _size = 7;
 
   @override
@@ -73,9 +99,15 @@ class JetpackRampArea extends RampArea {
     ]);
 }
 
+/// {@template jetpack_ramp_area_callback}
+/// Implementation of [RampAreaCallback] to listen when a [Ball]
+/// gets into a [JetpackRampArea].
+/// {@endtemplate}
 class JetpackRampAreaCallback extends RampAreaCallback<JetpackRampArea> {
+  /// {@macro jetpack_ramp_area_callback}
   JetpackRampAreaCallback() : super();
 
+  /// Collection of balls inside [JetpackRamp].
   final _ballsInsideJetpack = <Ball>{};
 
   @override
diff --git a/lib/game/components/pathway.dart b/lib/game/components/pathway.dart
index 7e67ee5a..8546a9ed 100644
--- a/lib/game/components/pathway.dart
+++ b/lib/game/components/pathway.dart
@@ -14,10 +14,10 @@ class Pathway extends BodyComponent {
     Color? color,
     required Vector2 position,
     required List<List<Vector2>> paths,
-    int? maskBits,
+    int? categoryBits,
   })  : _position = position,
         _paths = paths,
-        _maskBits = maskBits ?? Filter().maskBits {
+        _categoryBits = categoryBits ?? Filter().categoryBits {
     paint = Paint()
       ..color = color ?? const Color.fromARGB(0, 0, 0, 0)
       ..style = PaintingStyle.stroke;
@@ -38,7 +38,7 @@ class Pathway extends BodyComponent {
     required double width,
     double rotation = 0,
     bool singleWall = false,
-    int? maskBits,
+    int? categoryBits,
   }) {
     final paths = <List<Vector2>>[];
 
@@ -61,7 +61,7 @@ class Pathway extends BodyComponent {
       color: color,
       position: position,
       paths: paths,
-      maskBits: maskBits,
+      categoryBits: categoryBits,
     );
   }
 
@@ -87,7 +87,7 @@ class Pathway extends BodyComponent {
     required double angle,
     double rotation = 0,
     bool singleWall = false,
-    int? maskBits,
+    int? categoryBits,
   }) {
     final paths = <List<Vector2>>[];
 
@@ -114,7 +114,7 @@ class Pathway extends BodyComponent {
       color: color,
       position: position,
       paths: paths,
-      maskBits: maskBits,
+      categoryBits: categoryBits,
     );
   }
 
@@ -134,7 +134,7 @@ class Pathway extends BodyComponent {
     required double width,
     double rotation = 0,
     bool singleWall = false,
-    int? maskBits,
+    int? categoryBits,
   }) {
     final paths = <List<Vector2>>[];
 
@@ -157,13 +157,13 @@ class Pathway extends BodyComponent {
       color: color,
       position: position,
       paths: paths,
-      maskBits: maskBits,
+      categoryBits: categoryBits,
     );
   }
 
   Vector2 _position;
   List<List<Vector2>> _paths;
-  int _maskBits;
+  int _categoryBits;
 
   @override
   Body createBody() {
@@ -179,9 +179,7 @@ class Pathway extends BodyComponent {
         );
       final fixtureDef = FixtureDef(chain);
 
-      body.createFixture(fixtureDef)
-        ..filterData.categoryBits = _maskBits
-        ..filterData.maskBits = _maskBits;
+      body.createFixture(fixtureDef).filterData.categoryBits = _categoryBits;
     }
 
     return body;
diff --git a/lib/game/components/sparky_ramp.dart b/lib/game/components/sparky_ramp.dart
index d23f7561..5f351a83 100644
--- a/lib/game/components/sparky_ramp.dart
+++ b/lib/game/components/sparky_ramp.dart
@@ -4,12 +4,22 @@ import 'package:flame/extensions.dart';
 import 'package:flame_forge2d/flame_forge2d.dart';
 import 'package:pinball/game/game.dart';
 
+/// {@template sparky_ramp}
+/// Represent the upper right yellow ramp for the game.
+///
+/// Group of [Component]s composed by a [Pathway.arc] as the ramp, and two
+/// [SparkyRampArea] at the entrance and exit of the ramp, to detect when
+/// a ball gets into/out of the ramp.
+/// {@endtemplate}
 class SparkyRamp extends PositionComponent with HasGameRef<PinballGame> {
   SparkyRamp({
     required Vector2 position,
   })  : _position = position,
         super();
 
+  final double _radius = 300;
+  final double _width = 80;
+  final double _angle = math.pi;
   final Vector2 _position;
 
   @override
@@ -18,10 +28,10 @@ class SparkyRamp extends PositionComponent with HasGameRef<PinballGame> {
       Pathway.arc(
         color: const Color.fromARGB(255, 251, 255, 0),
         position: _position,
-        radius: 300,
-        angle: math.pi,
-        width: 80,
-        maskBits: RampType.sparky.maskBits,
+        radius: _radius,
+        angle: _angle,
+        width: _width,
+        categoryBits: RampType.sparky.maskBits,
       ),
     );
     await add(
@@ -41,6 +51,12 @@ class SparkyRamp extends PositionComponent with HasGameRef<PinballGame> {
   }
 }
 
+/// {@template sparky_ramp_area}
+/// Implementation of [RampArea] for sensors in [SparkyRamp].
+///
+/// [RampArea] with [RampType.sparky] to filter [Ball]s collisions
+/// inside [SparkyRamp].
+/// {@endtemplate}
 class SparkyRampArea extends RampArea {
   SparkyRampArea({
     required Vector2 position,
@@ -50,11 +66,18 @@ class SparkyRampArea extends RampArea {
         _orientation = orientation,
         super(
           position: position,
-          maskBits: RampType.sparky.maskBits,
+          categoryBits: RampType.sparky.maskBits,
         );
 
+  /// Orientation of entrance/exit of [SparkyRamp] where
+  /// this [SparkyRampArea] is placed.
   final RampOrientation _orientation;
+
+  /// Rotation of the [RampArea] to place it right at the
+  /// entrance/exit of [SparkyRamp].
   final double _rotation;
+
+  /// Size of the [RampArea] placed at the entrance/exit of [SparkyRamp].
   final int _size = 7;
 
   @override
@@ -70,9 +93,14 @@ class SparkyRampArea extends RampArea {
     ]);
 }
 
+/// {@template sparky_ramp_area_callback}
+/// Implementation of [RampAreaCallback] to listen when a [Ball]
+/// gets into a [SparkyRampArea].
+/// {@endtemplate}
 class SparkyRampAreaCallback extends RampAreaCallback<SparkyRampArea> {
   SparkyRampAreaCallback() : super();
 
+  /// Collection of balls inside [SparkyRamp].
   final _ballsInsideSparky = <Ball>{};
 
   @override