diff --git a/code/modules/mob/living/carbon/monkey/monkey.dm b/code/modules/mob/living/carbon/monkey/monkey.dm
index f3abe83958..e48fc722cd 100644
--- a/code/modules/mob/living/carbon/monkey/monkey.dm
+++ b/code/modules/mob/living/carbon/monkey/monkey.dm
@@ -43,7 +43,7 @@
 
 /mob/living/carbon/monkey/ComponentInitialize()
 	. = ..()
-	AddElement(/datum/element/mob_holder, "monkey", null, null, null, SLOT_HEAD)
+	AddElement(/datum/element/mob_holder, "monkey", null, null, null, ITEM_SLOT_HEAD)
 
 
 /mob/living/carbon/monkey/Destroy()
diff --git a/code/modules/mob/living/silicon/pai/pai_shell.dm b/code/modules/mob/living/silicon/pai/pai_shell.dm
index 641ad6dde0..3734c7f1f2 100644
--- a/code/modules/mob/living/silicon/pai/pai_shell.dm
+++ b/code/modules/mob/living/silicon/pai/pai_shell.dm
@@ -99,7 +99,7 @@
 	current_mob_holder?.Detach(src)
 	current_mob_holder = null
 	if(possible_chassis[chassis])
-		current_mob_holder = AddElement(/datum/element/mob_holder, chassis, 'icons/mob/pai_item_head.dmi', 'icons/mob/pai_item_rh.dmi', 'icons/mob/pai_item_lh.dmi', SLOT_HEAD)
+		current_mob_holder = AddElement(/datum/element/mob_holder, chassis, 'icons/mob/pai_item_head.dmi', 'icons/mob/pai_item_rh.dmi', 'icons/mob/pai_item_lh.dmi', ITEM_SLOT_HEAD)
 	to_chat(src, "<span class='boldnotice'>You switch your holochassis projection composite to [chassis]</span>")
 
 /mob/living/silicon/pai/lay_down()
diff --git a/code/modules/mob/living/simple_animal/friendly/drone/_drone.dm b/code/modules/mob/living/simple_animal/friendly/drone/_drone.dm
index 43149e6ba7..726eda6c45 100644
--- a/code/modules/mob/living/simple_animal/friendly/drone/_drone.dm
+++ b/code/modules/mob/living/simple_animal/friendly/drone/_drone.dm
@@ -105,7 +105,7 @@
 	. = ..()
 	if(can_be_held)
 		//icon/item state is defined in mob_holder/drone_worn_icon()
-		AddElement(/datum/element/mob_holder, null, 'icons/mob/head.dmi', 'icons/mob/inhands/clothing_righthand.dmi', 'icons/mob/inhands/clothing_lefthand.dmi', TRUE, /datum/element/mob_holder.proc/drone_worn_icon)
+		AddElement(/datum/element/mob_holder, null, 'icons/mob/head.dmi', 'icons/mob/inhands/clothing_righthand.dmi', 'icons/mob/inhands/clothing_lefthand.dmi', ITEM_SLOT_HEAD, /datum/element/mob_holder.proc/drone_worn_icon)
 
 /mob/living/simple_animal/drone/med_hud_set_health()
 	var/image/holder = hud_list[DIAG_HUD]
diff --git a/code/modules/mob/living/simple_animal/friendly/lizard.dm b/code/modules/mob/living/simple_animal/friendly/lizard.dm
index f0d354ace1..dbcaed1ba2 100644
--- a/code/modules/mob/living/simple_animal/friendly/lizard.dm
+++ b/code/modules/mob/living/simple_animal/friendly/lizard.dm
@@ -26,7 +26,7 @@
 
 /mob/living/simple_animal/hostile/lizard/ComponentInitialize()
 	. = ..()
-	AddElement(/datum/element/mob_holder, "lizard", null, null, null, SLOT_HEAD) //you can hold lizards now.
+	AddElement(/datum/element/mob_holder, "lizard", null, null, null, ITEM_SLOT_HEAD) //you can hold lizards now.
 
 /mob/living/simple_animal/hostile/lizard/CanAttack(atom/the_target)//Can we actually attack a possible target?
 	if(see_invisible < the_target.invisibility)//Target's invisible to us, forget it