SHS and Lancer Tactical are known for making high quality products. This spring guide is made by Lancer Tactical but it is also OEM by SHS. The spring guide is mainly made for all types of Version 2 gearboxes. A very high quality product at a very affordable price. The spring guide is the most inportant peace of the puzzle. Without the spring Guide you airsoft rifle will not send bb's down range at your target. If your doing some type of high speed build this spring guide will help not give stress to your spring. Thus making it last longer and make the rounds per second a little faster than the normal non-moving spring guide.