diff --git a/tp4/src/main/kotlin/fmt/kotlin/fundamentals/Container.kt b/tp4/src/main/kotlin/fmt/kotlin/fundamentals/Container.kt
index 02198e9..7e1e8c2 100644
--- a/tp4/src/main/kotlin/fmt/kotlin/fundamentals/Container.kt
+++ b/tp4/src/main/kotlin/fmt/kotlin/fundamentals/Container.kt
@@ -17,4 +17,9 @@ class Barrel(
 
 class Tank(
     capacity: Int
-) : Container(capacity, 2000000..10000000)
\ No newline at end of file
+) : Container(capacity, 2000000..10000000)
+
+abstract class FixedVolumeContainer(capacity: Int) : Container(capacity, capacity..capacity)
+
+class Magnum : FixedVolumeContainer(150)
+class Bottle : FixedVolumeContainer(75)
\ No newline at end of file