This heavy duty Out the Front knife is very well constructed for this price range. The handle is all metal construction. The double action slide button on the front is extremely reliable. The speed of the spring seems above average. The action is also very smooth. There is none of the herky-jerky action that sometimes you see on value out the front knives. It is fast, although some of your very top line knives are faster. The blade is single edge, but can very easily be sharpened on the other side and made into a double edge knife. A great knife, and at the price, it is a steal of a deal.