Spring upgrade for the Nerf springer blaster to increase FPS and make the darts travel further and faster.
Strongly recommend to change it along with the plunger rod and tube in your springer blaster for increased durability and reliability.
Please be informed that with higher main spring load means the operation of the blaster would be harder depending on the spring load you upgrade to. This also means your blaster internal and external will be subjected to higher stress. Modify and upgrade your blaster responsibly!