diff --git a/filter-injector.lua b/filter-injector.lua
index 6f38e60..e605c9e 100644
--- a/filter-injector.lua
+++ b/filter-injector.lua
@@ -201,7 +201,7 @@ local function punch_filter(data, filtpos, filtnode, msg)
 				set_filter_formspec(data, filtmeta)
 			end
 
-			if type(msg.tags) == "table" then
+			if type(msg.tags) == "table" or type(msg.tags) == "string" then
 				item_tags = pipeworks.sanitize_tags(msg.tags)
 			elseif type(msg.tag) == "string" then
 				item_tags = pipeworks.sanitize_tags({msg.tag})
diff --git a/item_transport.lua b/item_transport.lua
index 7577741..ddf2a08 100644
--- a/item_transport.lua
+++ b/item_transport.lua
@@ -388,7 +388,7 @@ luaentity.register_entity("pipeworks:tubed_item", {
 		end
 		local found_next, new_velocity, multimode = go_next(self.start_pos, velocity, stack, self.owner, tags) -- todo: color
 		if pipeworks.enable_item_tags then
-			self.tags = #tags > 0 and pipeworks.sanitize_tags(tags) or nil
+			self.tags = #tags > 0 and tags or nil
 		end
 		local rev_vel = vector.multiply(velocity, -1)
 		local rev_dir = vector.direction(self.start_pos,vector.add(self.start_pos,rev_vel))
diff --git a/tubes/lua.lua b/tubes/lua.lua
index 50782bf..1fc9208 100644
--- a/tubes/lua.lua
+++ b/tubes/lua.lua
@@ -972,10 +972,10 @@ for white  = 0, 1 do
 				elseif type(msg) == "table" then
 					if pipeworks.enable_item_tags then
 						local new_tags
-						if type(msg.tags) == "table" then
-							new_tags = msg.tags
+						if type(msg.tags) == "table" or type(msg.tags) == "string" then
+							new_tags = pipeworks.sanitize_tags(msg.tags)
 						elseif type(msg.tag) == "string" then
-							new_tags = {msg.tag}
+							new_tags = pipeworks.sanitize_tags({msg.tag})
 						end
 						if new_tags then
 							for i=1, math.max(#tags, #new_tags) do