This Thumb Latch features a reversible design for use of left- or right-hand doors up to 1 ½” thick.   
NOTE: Generally used on an in-swing door so that the thumb bar is on the outside and the lock is on the inside. Can be used on an out-swing door but the thumb bar will be on the inside and the lock will be on the outside. Out-swing doors are not very common in residential construction but often used for closets.