I have gotten permission to copy and paste this useful information off another forum:- Most people will know that Rob Bayley's S4 survival knife he designed for Bear Grylls has been copied en masse by a Chinese company, complete with the Grylls logo. Here's how you tell them apart and why they are as far off from the original Bayley made knife as you can get. The sales pictures make them seem very good copies, but in reality, they really aren't. First up. The two together, Bayley at top: Just by this picture you can see major differences. The quality of construction and materials is miles apart. So lets look at the closer details: The Rob Bayley knife has a shaped metal guard and the fake has a basic, crudely shaped square one. The fake has gaps between the G10 slabs and guard and the G10 also sits higher to the guard on one side, and lower on the other on the fake. The handmade Bayley has perfect fit and lines. everything fits together well on Rob Bayleys knives. The serrated bladed Bayley guard is rounded compared to the plain version he makes, which has a more angular choil area. And again, is much more ergonomic than the fake, which is not finished off. The Bayley also has a shaped spine with a raised thumb ramp at the guard. The fake is completely flat and uneven in places. The fake (right) also has basic aluminium tubes holding on the slabs. The Bayley knife has tubular (4mm hole) loveless type handle bolts the thread end can be clearly seen. As you can see from the close ups of the G10 slabs, the fake is flat without any form or ergonomics in mind, while the Bayley is hand finished and shaped to fit the users hand for extended periods without causing blisters. use teh fake for more than a minute and you really know about it!! The edges on the Bayley are also shaped and ergonomic, while the fake is left unfinished and square, although a half hearted attempt and putting an angle on the edge of the slabs has occurred in some areas, but they must get bored easy as it is not consistent or even regular. Looking down the back of the knife, The G10 handles on the Bayley the front of the handle tapers off towards the guard while the fake is dead flat with no shaping at all. All Bayley Knives are etched on the spine. Later models also have a serial number. The iconic Bayley side grill/scoops run flat/parallel to the knifes tang on the real knife, while the fake has them scooped out. The Bayley knife also has a deep belly which lets you fingers lock into this grill On the fake, your fingers don't fall anywhere near them, so they are useless. They are far more subtle and finely machined on Rob Bayleys knife. The fake looks like someone was let loose with a Dremel. Rob Bayleys S4 is also made from RWL-34. The fake is made from AUS-8 and is clearly printed on the blade. The fake blade also has machine marks running vertically down it. Rob Bayleys knife is finely polished with a hand rubbed horizontal brushed finish. The Bear Grylls signature is also etched into the steel on a Bayley and in black. The fakes are printed in white/silver and uses kiddy font rather than bold caps found on the Bayley. Now the sheath. Where do you start here? The fake is made from awful, very thin leather and the knife point actually pokes through at the bottom after sheathing it a few times due to the multi layered and thin leather stacking. The Bear Grylls printing is crude and it is just the cheapest thing you can imagine. This Bayley one next to it is four years old and in better condition, made from thick saddle leather and finished as you'd expect from a custom knife maker. You get what you pay for. But don't be fooled by people who say it is the same. It is a world apart and feels completely different in the hand. The heat treat on the fake is also inconsistent and it is pure luck if you get one that will hold an edge and not roll. This one I tested developed a bent tip up to 1cm up after prising off dead birch bark. It is no Bayley knife. Fit, form and function are different, as are ergonomics and even the overall shape. It looks like a Bayley in the pictures advertising it. But believe me, it is as different as the cheapest of Chinese SAKs compared to a Victorinox, but even more so.