diff --git a/libraries/render-utils/src/simple.slf b/libraries/render-utils/src/simple.slf
index 5ad9dc174f..0f848ee231 100644
--- a/libraries/render-utils/src/simple.slf
+++ b/libraries/render-utils/src/simple.slf
@@ -18,7 +18,7 @@
 // the interpolated normal
 in vec3 _normal;
 in vec3 _modelNormal;
-in vec3 _color;
+in vec4 _color;
 in vec2 _texCoord0;
 in vec4 _position;