With this, Gripknife will attach to any rail system. Gripknife mounts directly to a picatinny rail; if your firearm does not have this, but instead uses MLok or KeyMod, this is the part you need to attach Gripknife to your firearm.
 
Features
5-slot KeyMod / M-LOK picatinny rail section featuring a standard 3/8" QD swivel socket (swivel not included).
Accessory rail section with an swivel, for both KeyMod and M-LOK hand guards
Push button QD Sling swivel included (detachable) 
Use as a regular Picatinny accessory rail section without the swivel
Ideal for attaching lights, laser, optics, bipods, and forward grips
Lightweight rails, made of aluminum with black anodized matte finish
Mounting screws and tools included
Easy to install
 
Specifications
Material: Aluminum Alloy, Steel
Color: Black (Rail), Brushed Nickel (QD Sling Swivel)
Slot: 3-slot / 5-slot / 8-Slot / 10-Slot for Option
Length: 2" (3-slot), 3" (5-slot), 3 7/8" (8-slot), 4 7/8" (10-slot)
Mount: 20mm Picatinny Rail
 
Package Included
One (1) KeyMod/M-LOK Picatinny Rail Section with Sling Swivel (Pick your size)
One (1) Allen Wrench
Two (2) mounting screws
Two (2) KeyMod mounting nuts
Two (2) M-Lok mounting nuts