TechWell Magwell System is a great option for your 1911 Pistol.
The Magwell snaps on the bottom and has two tabs that interface with the grip. It has many grip options and is easy to install. This is a close up video of the product. You can see some of the grip options and colors. It does comply with USPSA, IDPA and IPSC standards.
For more information: https://www.shootersconnectionstore.com/Gun-Parts-C313.aspx?m=58
Let me know what you think of the video or if you have the TechWell Magwell System and would like to share your thoughts, please comment.