diff --git a/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaCircular.java b/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaCircular.java
index 15de4dc..9b5aaa8 100644
--- a/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaCircular.java
+++ b/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaCircular.java
@@ -28,4 +28,8 @@ public T peek() {
         return null;
     }
 
+    public LinkedList<T> extricate() {
+        return inner;
+    }
+
 }
diff --git a/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaLineal.java b/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaLineal.java
index 3ee3425..8febb49 100644
--- a/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaLineal.java
+++ b/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEColaLineal.java
@@ -29,4 +29,8 @@ public T peek() {
         }
         return null;
     }
+
+    public LinkedList<T> extricate() {
+        return inner;
+    }
 }
diff --git a/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEPila.java b/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEPila.java
index 61e4cba..4937d58 100644
--- a/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEPila.java
+++ b/src/main/java/com/utp/clsEstructuraDatos/Estructuras/linked_list/LEPila.java
@@ -57,4 +57,7 @@ public boolean isFull() {
         return false;
     }
 
+    public LinkedList<T> extricate() {
+        return inner;
+    }
 }
diff --git a/src/main/java/com/utp/clsEstructuraDatos/laboratorio_4/Main.java b/src/main/java/com/utp/clsEstructuraDatos/laboratorio_4/Main.java
new file mode 100644
index 0000000..22aea35
--- /dev/null
+++ b/src/main/java/com/utp/clsEstructuraDatos/laboratorio_4/Main.java
@@ -0,0 +1,169 @@
+package com.utp.clsEstructuraDatos.laboratorio_4;
+
+import java.util.Optional;
+
+import com.utp.clsEstructuraDatos.Estructuras.linked_list.LEColaCircular;
+import com.utp.clsEstructuraDatos.Estructuras.linked_list.LEColaLineal;
+import com.utp.clsEstructuraDatos.Estructuras.linked_list.LEPila;
+import com.utp.clsEstructuraDatos.Estructuras.linked_list.LinkedList;
+
+public class Main {
+
+}
+
+class App {
+    static final String LABORATORIO = "Laboratorio 4";
+    Optional<AppCollection<Integer>> collection;
+
+    void new_collection() {}
+
+}
+
+sealed interface AppCollection<T> {
+    // @formatter:off
+    void insert(T element);
+    Optional<T> pop();
+    Optional<T> peek();
+    boolean isEmpty();
+    boolean isFull();
+    void clear();
+    int len();
+    default AppCollection<T> extend_from(AppCollection<T> source){
+        switch (source) {
+            case Stack<T>(var stack) -> {
+                var element = stack.extricate
+                this.insert()
+            }
+            case Queue<T>(var queue) -> {
+                for (int i = 0; i < list.len(); i++) {
+                    queue.insert(list.get(i).get());
+                }
+                return new Queue<>(queue);
+            }
+            case CircularQueue<T>(var circular_queue) -> {
+                for (int i = 0; i < list.len(); i++) {
+                    circular_queue.insert(list.get(i).get());
+                }
+                return new CircularQueue<>(circular_queue);
+            }
+        }
+    }
+    // @formatter:on
+
+    public record Stack<T>(LEPila<T> pila) implements AppCollection<T> {
+
+        @Override
+        public void insert(T element) {
+            pila.push(element);
+        }
+
+        @Override
+        public Optional<T> pop() {
+            return Optional.ofNullable(pila.pop());
+        }
+
+        @Override
+        public Optional<T> peek() {
+            return Optional.ofNullable(pila.peek_top());
+        }
+
+        @Override
+        public boolean isEmpty() {
+            return pila.len() == 0;
+        }
+
+        @Override
+        public boolean isFull() {
+            // Since LEPila is backed by a LinkedList, it's never full.
+            return false;
+        }
+
+        @Override
+        public void clear() {
+            pila.clear();
+        }
+
+        @Override
+        public int len() {
+            return pila.len();
+        }
+    }
+
+    public record Queue<T>(LEColaLineal<T> lineal_queue) implements AppCollection<T> {
+
+        @Override
+        public void insert(T element) {
+            lineal_queue.insert(element);
+        }
+
+        @Override
+        public Optional<T> pop() {
+            return Optional.ofNullable(lineal_queue.remove());
+        }
+
+        @Override
+        public Optional<T> peek() {
+            return Optional.ofNullable(lineal_queue.peek());
+        }
+
+        @Override
+        public boolean isEmpty() {
+            return lineal_queue.len() == 0;
+        }
+
+        @Override
+        public boolean isFull() {
+            // Since LEColaLineal is backed by a LinkedList, it's never full.
+            return false;
+        }
+
+        @Override
+        public void clear() {
+            lineal_queue.clear();
+        }
+
+        @Override
+        public int len() {
+            return lineal_queue.len();
+        }
+    }
+
+    public record CircularQueue<T>(LEColaCircular<T> looped_queue) implements AppCollection<T> {
+
+        @Override
+        public void insert(T element) {
+            looped_queue.insert(element);
+        }
+
+        @Override
+        public Optional<T> pop() {
+            return Optional.ofNullable(looped_queue.remove());
+        }
+
+        @Override
+        public Optional<T> peek() {
+            return Optional.ofNullable(looped_queue.peek());
+        }
+
+        @Override
+        public boolean isEmpty() {
+            return looped_queue.len() == 0;
+        }
+
+        @Override
+        public boolean isFull() {
+            // Since LEColaCircular is backed by a LinkedList, it's never full.
+            return false;
+        }
+
+        @Override
+        public void clear() {
+            looped_queue.clear();
+        }
+
+        @Override
+        public int len() {
+            return looped_queue.len();
+        }
+    }
+}