Review on Quick Release Magnetic Bit Holder Extension Set - 10 Pieces With 1/4 Inch Hex Shank For Screws, Nuts, Drills, Handheld Drivers - Heavy Duty With Various Lengths (50/60/75/100/150Mm) by Brian Graham

You get a lot of extensions for your money with this pack. The set comes in 2 cheap ziploc bags but you're not buying these for the packaging. The steel looks to be adequate but clearly not high end. Because these types of tools are often lost or abused, the low price may be the greatest strength of this set.The sockets are rather deep which is good for attaching extensions together for greater reach but bad if you are using a short bit. (it will swallow most of the bit making it difficult to remove)These are not high end tools but they are cheap. There is no lock on the socket, the bit is held in by magnectic force and the sockets do not appear to be hardened steel. I suspect these will not take a lot of force before they fail. You do get two of each size.Bottom line - If your work involves the possibility of losing a tool or two, these may be just the ticket. I'd rather lose a $1 extension than a $10 one. If you need a good quality extensions for critical work, these are not your best choice.