Our New Vented Stone Krusher Flat Spiked extension for the MPA 9mm with 1/2x28 Threads offers a new design and length. For door breach, defense and barrel counterbalance. This machined aluminum vented extension is finished in flat black anodize, 7 inches in length, 1.5" OD, and weighs about 14 ounces. Threaded in 1/2x28. **4th photo shows the 1/2x28 threads for reference**
