Combine over hot (not boiling) water, milk chocolate morsels and vegetable shortening; stir until morsels melt and mixture is smooth. Remove from heat but keep chocolate over hot water. Dip pretzels into chocolate mixture and coat evenly; shake off any excess coating. Place pretzels on waxed paper-lined cookie sheets. Chill in refrigerator until coating sets (about 15 minutes). Gently loosen from waxed paper. Serve immediately or store in refrigerator until ready to serve. Makes about 50 dipped pretzels