diff --git a/hb_server/apps/mtm/serializers.py b/hb_server/apps/mtm/serializers.py
index d512b57..04f3e3d 100644
--- a/hb_server/apps/mtm/serializers.py
+++ b/hb_server/apps/mtm/serializers.py
@@ -18,7 +18,7 @@ class MaterialDetailSerializer(serializers.ModelSerializer):
     
     def get_processes_(self, obj):
         steps = UsedStep.objects.filter(subproduction__product=obj).values_list('step', flat=True)
-        objs = Process.objects.filter(step_process__id__in=steps).order_by('number')
+        objs = Process.objects.filter(step_process__id__in=steps).distinct().order_by('number')
         return ProcessSimpleSerializer(instance=objs, many=True).data