C&H Precision V4 Optic Mounting Adapter Plate For Echelon to Holosun 407K/507K and C&H EDC Anodized Finish Black. Each plate is precision machined to the tightest tolerances on HAAS CNC machines and each plate goes through multiple quality checks before shipping. Specifications for C&H Precision Weapons V4 Optic Mounting Plate Springfield OSP Adapter Plate: Manufacturer: C&H Precision Weapons Red Dot Sights-Footprint: Holosun K Optic Cut: Springfield OSP Fabric/Material: Aluminium Color: Black Gun Model: Springfield Armory Echelon Finish: Anodized Gun Make: Springfield Armory Package Contents: C&H Precision Weapons V4 Optic Mounting Plate Springfield OSP Adapter Plate What firearm models does the manufacturer say C&H Precision Weapons V4 Optic Mounting Plate Springfield OSP Adapter Plate is compatible with? The manufacturer suggests that C&H Precision Weapons V4 Optic Mounting Plate Springfield OSP Adapter Plate is compatible with Springfield Armory Echelon