diff --git a/src/Events.php b/src/Events.php
index dc0fa40..86ffed6 100644
--- a/src/Events.php
+++ b/src/Events.php
@@ -175,7 +175,7 @@ private function output(callable $type): EntryCollection|LengthAwarePaginator
                 return $occurrence
                     ->setSupplement('start', $start)
                     ->setSupplement('end', $end)
-                    ->setSupplement('spansDay', ! $start->isSameDay($end));
+                    ->setSupplement('spans_days', ! $start->isSameDay($end));
             });
         }
 
diff --git a/tests/Tags/EventsTest.php b/tests/Tags/EventsTest.php
index 5cf04da..ca42b5f 100755
--- a/tests/Tags/EventsTest.php
+++ b/tests/Tags/EventsTest.php
@@ -428,7 +428,7 @@
         ->first()->start->timezone->getName()->toBe('America/Vancouver');
 });
 
-it('sets "spansDay"', function () {
+it('sets "spans_days"', function () {
     Carbon::setTestNow(now()->setTimeFromTimeString('10:00'));
 
     Entry::make()
@@ -454,5 +454,5 @@
     $occurrences = $this->tag->between();
 
     expect($occurrences)->toHaveCount(1)
-        ->first()->spansDay->toBeTrue();
+        ->first()->spans_days->toBeTrue();
 });