While we've been mentioning the AT4 replica for airsoft use in recent news posting, we are not done yet as UN Company also has an ACM of it in stock. Also, they have several slide sets for the Tokyo Marui PX4 Gas Blowback airsoft pistol that you might want to consider when upgrading your backup pistol... "Dear All, UN Company wants to introduce some new products that we got this week:

China made AT4 /M136 Grenade Launcher

Taiwan Metal Slide Full Set for Marui PX4 (SV)
Taiwan Metal Slide Full Set for Marui PX4 (BK)
UN Custom-Marui PX4 Taiwan Metal Slide Ver. (BK)
UN Custom-Marui PX4 Taiwan Metal Slide Ver. (SV)

Please visit our site http://www.uncompany.com for more new hot items. You may also found more airsoft products you need there. Enjoy!"