This rifle length SPR Straight top rail is a full Picatinny rail that connects the receiver to the forearm. This top requires the 8.5" rail with lugs in order to connect top rail to forearm. This creates a rigid platform ideal for mounting accessories. This top rail works with both the Gen II round forearms as well as the Octagonal forearm with M-LOK.
AR15 SPR 15 Straight Top Rail for Gen III Delta Forearms
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AR15 SPR 15 Top Rail for Gen III Round Forearms
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