To take care of the scope mounting problems with short or long stocks. Gives .660" (16.8mm) greater forward or rearward ring placement.
SPECS:
Steel, 1" (2.5cm) or 30mm (1.2") diameter. Available in Polished Blue (PB) or Matte Blue (MB). Heights shown are from top of base to inside bottom of ring: 1" (2.5cm), Med. .272" (6.9mm), High .402" (10.2mm), 30mm (1.2"), Med. .312" (7.9mm), High .490" (12.5mm).
Catalog page 251