Review on Boost Efficiency with the CONFAST Inside Diameter Machine Setting by Justin Gerrero

I used the 1/4 and 1/2 combination drill bit used for shutters to drill a hole for them. They're sitting pretty tight. The combination drill has a stopper so you get the perfect drill depth every time. If you're using a regular 1/2 masonry bit, your hole is likely to be a bit larger and the anchors won't go in as firmly as with a combination bit. I live in Florida and have combo beats at my local store, but I'm pretty sure Revane has them too. Another piece of advice. They CAN be used in hollow concrete block walls. Your manufacturer has kindly provided a hammer tool for IN THE BOX installation which CANNOT be used if you are installing in a hollow block. I suggest a quality cavity wall installation tool like Greenlee suggested by Revain. HOWEVER, I made my own using a 1/4 - 20 machine screw and a 1/4 thru hole bronze bushing. I hold the bushing with a vise, a pair of pliers uses a cordless drill on the machine screw to pull the cone forward into the hole and expand the line. WASH HANDS AND TOOLS when finished. These are lead. DO NOT make the mistake of putting them in the hole upside down. They will last for a while, and then whatever you have attached to the wall will collapse. The small cone enters the hole FIRST. For your health!