Combining Text And Value In Trigger

Hi,

I have written a trigger that emails a specified person.

I am trying to include a body of the email which comprises of the stock level and a warning. Pulling out my hair...Help

Code so far in the trigger is :

CREATE TRIGGER Warnings ON [dbo].[tbl_sql_cartridges_kh]
for update
AS
declare @SL as int
declare @SS as int
declare @Msg as nvarchar(100)
set @SL= (select stock_level from inserted)
set @SS =(select cartridge_key from inserted)
set @Msg = 'Print Cartridges Level Warning'
if @SL < 3
begin

exec sp_send_cdontsmail 'Print-Cartridges','XXX@XXXX.co.uk','Print Cartridges Level Warning',@Msg
end

I would like the @Msg to say something like Cartridge XXX stock level is YYY, where XXX and YYY are taken from the table after update. I can get the values, but cant put them in the MSG string..

Like @msg & @SL (SL being Stock Level)

Many Thanks

Ken