Abstract: The construction of a flexographic printing mat specially shaped to enhance its snug and continued engagement over its full length to a magnetic base cylinder. The flexographic printing mat is made of shim stock steel and is preformed with inverted V-shapes lying parallel to and closely adjacent both of its ends to form closely spaced apart cylinder engaging lines at each end of the mat. The spaced apart line contacts of the mat with the magnetic cylinder act to concentrate the gripping power of the cylinder to securely hold the mat and including its leading and trailing ends to the cylinder.