diff --git a/back/object/models.py b/back/object/models.py
index 0aa39d9..f4444d5 100644
--- a/back/object/models.py
+++ b/back/object/models.py
@@ -1,4 +1,5 @@
 from django.db import models
+from django.core.validators import MinValueValidator, MaxValueValidator
 import logging
 
 logger = logging.getLogger("root")
@@ -16,6 +17,16 @@ class Element3D(models.Model):
     model_file = models.FileField(upload_to=group_based_upload_to)
     name = models.CharField(max_length=255)
     description = models.TextField()
+    min_distance = models.IntegerField(
+        validators=[MinValueValidator(1), MaxValueValidator(200)],
+        blank=True,
+        null=True
+    )
+    max_distance = models.IntegerField(
+        validators=[MinValueValidator(2), MaxValueValidator(200)],
+        blank=True,
+        null=True
+    )
 
     def __str__(self):
         return self.name
diff --git a/back/package-lock.json b/back/package-lock.json
new file mode 100644
index 0000000..6515d94
--- /dev/null
+++ b/back/package-lock.json
@@ -0,0 +1,6 @@
+{
+  "name": "back",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {}
+}