Cleveland Golf Mashie Individual Iron Gliderail Sole Design Technology A- Measurably less turf drag, increased lift and speed at impact from any lie. B- More distance, versatility and accuracy  especially from the rough. Combo hybrid and iron set A- Optimized set makeup (3-5 hybrid; 6-9 iron; PW, DW, SW) for versatility and ideal distance gapping. B- Maximized distance and forgiveness for all shots required for each club. Progressive Sole Design A- Gliderail technology and sole design are customized for each specific iron and its function. B- Optimized playability throughout the set. Additional Features: RetroRaw finish, RetroSock headcover on hybrids.