The DEWALT DT99591 FlexVolt XR Poroton Blades are well suited to the cutting of standard class 12 clay blocks as well as various other materials such as general masonry, concrete and block. Their extreme runtime design enhances durability doubling the blades life span. Compatible with the DEWALT FlexVolt Alligator Saw 54 Volt. Can also be used with other DEWALT Models DWE397, DWE398 & DWE399.