Shipping costs are based on an estimate of UPS ground or equivalent carrier within the contiguous US, excluding Alaska and Hawaii. Please see Seller's website for actual shipping costs.
Details of J P Enterprises Ar-15 Alternate 5 Spring Pack For Jpscs-15
The Alternative Spring Pack Kits are a pack of 5 different spring weights for the JP Silent Captured Spring that allow custom tuning of the device to a given rifle. While the default spring offers the best performance for the widest range of configurations, a simple disassembly and reassembly of the JPSCS-15 with a slightly different spring rate can yield truly optimized performance, particularly for rifles without an adjustable gas block. Mfg: J P Enterprises