(S)keletonized(T)ube(5)inches long and 5 positions 

This M4 tube adapter replaces the standard buffer tube to ensure the stock folds as flat as possible! (With proper folding adapter)

The ST-5 was designed specifically to allow stocks such as the LWRC Ultra Compact Stock to collapse all the way up to the folding mechanism for a shorter overall length and profile. The ST-5 is the perfect option for compact stocks and braces! 

Fits most M4 style stocks/braces 

Lightweight and Rigid

• Integrated QD Sling Sockers
• 5" Length
• 5 positions 
• Compatible with SIG folding mechanisms
• 7075 T6 Aluminum
• Type III Hardcoat Anodized

SM-4.5 adapters utilize the factory rear trunnions and eliminate the need for additional adapters or folding mechs. 

This version of the SM stock/brace adapter is specifically made for 4.5mm pin folding stocks. 4.5mm trunnions can be found in the SLR 104/106/107 UR/CR/FR. This stock adapter, like the rest of the SM line, will allow you to install all of our Arm Bar and Stocks as well as SIG style stocks. Cheek wield is adjustable by moving the stock/brace up or down on the adapter.

• 2 height positions
• Compatible with all of our SS/AB/ST options as well as SIG stocks
• 7075 aluminum
• Black hardcoat anodize finish
• Includes mounting bolt for lower hole

*May require fitting on Palmetto State Armory 4.5mm trunnions.

*Does not lock in the folded position. (See RSA-4.5 + FM-SM-1913 Folding Mech if you require your stock/brace to lock when folded)