[ullie]

..if you go to the Magpul website...under rifles...click on UBR...when a new window opens click on the related information button...just in case the linky doesn't work for you...

...here's a PDF with detailed information and install instructions...

... http://store.magpul.com/downloads/ubr-final_web.pdf

 

[ullie]

...copy and paste Quote from Magpul below...

"NOTE: The UBR includes the necessary Entry-Length Receiver Extension tube and all mounting hardware. An M4 Carbine Buffer and Spring are required for use with the UBR and are not included."

...this is a quote from the Magpul website...everything is included in the package...you DO NOT need the "carbine buffer and spring" when installing the UBR on the Sig 556...the carbine buffer and spring are part of the operating system on an AR...the Sig 556 doesn't have the carbine buffer or spring....it has the recoil spring around the gas piston...

...just a heads up...
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