TheBob Burns Limited Edition, low deep CG (center of gravity) stainless irons are designed to position the center of gravity as close to the sole (low) and as far away from the face as deep as possible. The advantage of a low and deep CG is that more club head mass lies under the equator of the golf ball at impact, thus assisting higher launch angles without the need for high-spinning golf balls. The deep CG placement influences a greater transfer of energy at impact. As it turns out, energy transfer increases as the CG moves farther away from the face. The undercut channel is very effective in moving the mass away from the face while also distributing weight from heel to toe around the center of the club. Clubs hit high on the toe and low in the heel will have a greater gear-effect. A ball hit on the heel the ball will fade, and a ball hit on the toe will draw each back toward the center of the green. 

PGA Master Professional Irons