DHS500XT18 Diablo 18 in x 7/16 in Universal Extension Diablo’s Universal Extensions provide access in hard to reach areas by extending the length of your power tool accessory. No tools are required with this extension in order to attach accessories, the quick-change feature allows users to switch between accessories with no down time. These extensions are ideal for use with Diablo’s Snap-Lock Plus Hole Saw Mandrel.Extend reach in hard to access areasIdeal for Diablo Snap-Lock Plus Hole Saw MandrelEffortlessly switch between accessories and sizesNo tools requiredIdeal For: Extending the reach in hard to access areas