diff --git a/code/modules/research/xenobiology/xenobiology.dm b/code/modules/research/xenobiology/xenobiology.dm
index 0e02e7ee..bf127549 100644
--- a/code/modules/research/xenobiology/xenobiology.dm
+++ b/code/modules/research/xenobiology/xenobiology.dm
@@ -845,7 +845,7 @@
 		return
 	if(isitem(C))
 		var/obj/item/I = C
-		if(I.slowdown <= 0 || I.obj_flags & IMMUTABLE_SLOW)
+		if(I.slowdown <= 0 || I.obj_flags == IMMUTABLE_SLOW)
 			to_chat(user, "<span class='warning'>The [C] can't be made any faster!</span>")
 			return ..()
 		I.slowdown = 0