Belle River Bogey Golfer

OK, Thank you. I came across your posts from a Google search looking to compare M4's to Speed Blades. I've played golf for about 7 years now, had a cheapie set of Tommy Armours and then bought a new set of Speed Blades (steel shafts). I've gone from an 18 to 8 with the Speed Blades, great clubs!!! I've just bought a set of M4's (don't really know why) but fully intend on keeping the Speed Blades and go back and forth.

What are "MB" irons, I got that GI means game improvement but I don't know what MB stands for??