The Modern adjustable riser features a 7-3/4" Mitchell top plate as well as a 7-3/4" bottom plate. The top plate features (4) female key-way's. The bottom plate includes a Mitchell thread, Mitchell castlenut, as well as (1) male key-way.
This riser includes (8) 1-1/2" female receivers. Using standard 1-1/2" schedule 40/80 Speed-Rail, options for this riser are limitless. Speed-Rail® not included.