The spring tool, BamBam, makes the task of inserting large grommets very easy. This tool illiminates having to use small brads or the small grommet to make connections into tape wire. One end has a center punch and the other end has a pin that a large grommet can slip over. Place the grommet where it needs to be inserted, pull back on the spring, and let it slam down inserting the grommet into the tape wire and backing. Even works with high density board (mdf).