The VLTOR IMOD (Improved Modstock) is a very popular buttstock for owners who want extreme durability and reliability for their carbine. The IMOD has a "solid" feel with a comfortable, wide design that provides significant area for a comfortable cheek weld.  It features dual accessory compartments for spare batteries or parts, a removable buttpad and an angled toe at the bottom of the butt. Buttstock includes IMOD stock and accessory compartment.

Link to parts manufacturer