LT-Valve assembly - (300-400psi ) Medium pressure valve 1200 psi max Maximizes consistency, accuracy and reliability . Handles 3000 psi without damage. A tuned pin with a tapered head reduces turbulence while entering the valve guide. The smaller head also increases the valve chamber storage space The guide itself is also low turbulence drilled. We also included a "Burst Pocket" to reduce the psi curve and increase accuracy. The brass valve guide reduces drag on the hardened stainless steel valve pin. Its the last valve you should ever have to buy. Works with a wide range of hammer springs. Valve spring not included.