KAK INDUSTRY AR15 SIG SB-15 DEDICATED PISTOL BUFFER TUBE Accepts Sig SB-15 Pistol Braces length- 8.45" from the end of reciever Weight 7.8oz Finish- Black Military Hard Coat Anodize Uses Modified end plate (index tab removed) and Milspec castle nut Accepts AR15 buffers and springs FOR THOSE WHO HAVE NOT USED THIS TYPE OF TUBE BEFORE, NO LOCK NUT IS REQUIRED AS THE TUBE SHOULDERS ITSELF ON THE RECEIVER. ALSO THE ENDPLATE MUST HAVE THE ALIGNMENT TAB REMOVED OR GROUND DOWN TO ALLOW THE TUBE TO SPIN FREELY THROUGH IT. KAK INDUSTRY QD PISTOL VERSION ENDPLATES ARE AVAILABLE FROM US DIRECTLY AS WELL JUST ASK FOR PISTOL VERSION.. DEDICATED SIG SB15 ENHANCED TUBE THAT FEATURE A DEDICATED DIAMETER FOR THE SIG SB-15 ARM BRACE, EXTENDED LENGTH FOR MORE SUPPORT ON YOUR ARM, LARGER SHOULDER DIAMETER FOR INCREASED LOCKUP SURFACE FOR EXTRA STRENGTH AND STIFFNESS. THIS BUFFER TUBE SYSTEM IS PATENT PENDING