Does what it says on the box! I managed to get my handplane blades sharp enough to plane 5" x 5" oak end grain (see pic). More detail below Once figured out it takes under a minute to get the blade in the guide, and about 20 seconds per stone to top up a micro bevel and get back to work. Some say freehand is quicker, but for a mortal hobbyist I believe the time spent setting up the guide pays back in leaps and bounds. And the price is fair for a piece of Veritas quality that is serviceable with backup parts and should last a long time. I am a (ambitious) beginner and have been dabbling with hand tools (read: I have 20 chisels and 5 handplanes, and I use them all). Thought I would sharpen freehand, as I've been sharpening kitchen knives freehand for about 15 years. But I soon discovered a few things (mostly credited to Ron Hock): (1) In a plane blade needs clearance, which in simple terms means that your sharpening angle needs to remain low enough. With repeated microbevel resharpenings by hand, the angle tends to increase, and eventually my plane blades didnt have enough clearance to cut. It was at this point that I gave up and bought this guide (2) A durable chisel edge (and bevel) needs to be finished in a fine grit if it is to remain sharp for a while. When sharpening freehand, its really difficult to keep an accurate angle while moving between grits. (3) Its really difficult (and tiring) to regrind a new bevel on an old edge freehand. After all these hard-learnt lessons, I bought the angle guide and never looked back. I used it to set new bevels on old edges on 80 grit sandpaper stuck to melamine with double sided tape, and I used it to create polished micro bevels using a set of cheap diamond stones off amazon, a spray can with water, and a rag to clean the blade and stones between grits. And now I take whisper thin shavings, or really thick ones, and I chop mortises in hardwood like my name is Andre Roubo.