Remo Dynamo 3-Pack Hole Saver Black DynamOs bass drum hole cutting templates Available in black or white in packs with a 5, 7, and 9 inch templates or single 5 inch template Remo Dynamo Hole Savers are easy-to-apply microphone hole templates They allow the bass drum to be ported for a dry sound, and provides for repeated microphone placement without fear of ripping the exposed edge of the microphone hole Sizes 5", 7", and 9"