SWITCHBLADE? 10 Blade Replacement Kit – 1-3/8″ Get the replacement blade that makes your Milwaukee? 1-3/8″ SWITCHBLADE? Selfeed Bit instantly new. Milwaukee SWITCHBLADE? Replacement Blades are made of hardened steel for long life. They’re easy to change out, so you?re always ready for faster drilling and less downtime on the job. The 1-3/8″ SWITCHBLADE? Replacement Blade Kit includes 10 replacement blades, 2 feedscrews, 2 set screws, 1 hex wrench, and storage case.