The MS:9 and MS:45 are built for those who want or need modularity in their pistol caliber platforms. The freedom of choice is nice but sometimes it's a necessity. - The MS:9 allows you to configure them short or long depending on your application. - Equally at home on pistols or PCC's they have no barrel length restrictions regardless of your rate of fire. Plus they are easy to disassemble with common garage tools. Combine that with stainless steel baffles and you have no excuse to not clean the suppressor when needed. - Calibers : 9mm - Mount : Ships with 1/2-28 piston - Outer Diameter : 1.375 inches - Material Composition : 7-4 Stainless steel baffles 7075 aluminum tube - Weight: 8.7oz (Short) 10.5oz (Long) - Length : 5.375 inches (Short) 7.5 inches (Long) - Finish : Cerakote DLC (Diamond-like coating)