diff --git a/composer.json b/composer.json
index 0d1d9f6e95..305e67c676 100644
--- a/composer.json
+++ b/composer.json
@@ -95,7 +95,10 @@
     "autoload": {
         "psr-4": {
             "Atk4\\Ui\\": "src/"
-        }
+        },
+        "files": [
+            "demos/EntityFieldPair.php"
+        ]
     },
     "autoload-dev": {
         "psr-4": {
diff --git a/demos/EntityFieldPair.php b/demos/EntityFieldPair.php
new file mode 100644
index 0000000000..d7553e2a09
--- /dev/null
+++ b/demos/EntityFieldPair.php
@@ -0,0 +1,87 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Atk4\Data\Model;
+
+use Atk4\Core\WarnDynamicPropertyTrait;
+use Atk4\Data\Field;
+use Atk4\Data\Model;
+use Atk4\Ui\Demos\WrappedId;
+
+/**
+ * @template-covariant TModel of Model
+ * @template-covariant TField of Field
+ */
+class EntityFieldPair
+{
+    use WarnDynamicPropertyTrait;
+
+    /** @var TModel */
+    private $entity;
+    /** @var string */
+    private $fieldName;
+
+    /**
+     * @param ModelWithPrefixedFields $entity
+     */
+    public function __construct(Model $entity, string $fieldName)
+    {
+        $entity->assertIsEntity();
+
+        $this->entity = $entity;
+        $this->fieldName = $fieldName;
+    }
+
+    /**
+     * @return ModelWithPrefixedFields
+     */
+    public function getModel(): Model
+    {
+        return $this->entity->getModel();
+    }
+
+    /**
+     * @return ModelWithPrefixedFields
+     */
+    public function getEntity(): Model
+    {
+        return $this->entity;
+    }
+
+    public function getFieldName(): string
+    {
+        return $this->fieldName;
+    }
+
+    /**
+     * @phpstan-return TField
+     */
+    public function getField(): Field
+    {
+        $field = $this->getModel()->getField($this->getFieldName());
+
+        return $field;
+    }
+
+    /**
+     * @return WrappedId|null
+     */
+    public function get()
+    {
+        return $this->getEntity()->get($this->getFieldName());
+    }
+
+    /**
+     * @param WrappedId $value
+     */
+    public function set($value): void
+    {
+        $this->getEntity()->set($this->getFieldName(), $value);
+    }
+
+    public function setNull(): void
+    {
+        $this->getEntity()->setNull($this->getFieldName());
+    }
+}