Kerm-Lock Universal Rail Adapter: Making Standard Hand-guards Modular Again
Kac M4 Carb Rail Adapter System 556 low price of $250.73
Matrix AK to M4 Conversion Key Adapter (For AK Airsoft AEG to use M4 Series Front End), Accessories & Parts, External Parts, AK External Parts, AK Conversion Kits - Evike.com Airsoft Superstore
FGR 3 - M4 / AR15 Polymer Tri-Rail Handguard | Israel Defense Store
KAC M4 Rail Adapter System- MOD Armory
Artisan New Type M4 Folding Stock Adapter For MCX / M1913 20mm Rail ( Black / DDC )
Creation Airsoft Picatinny Rail Mount for M4 Style Carry Handles - Fox Airsoft LLC
M4 RAS Forend Assembly - Knight's Armament
RAP4 M4 Scope Mount Base [mounts to M4 Carry Handle]