I understand that it's supposed to make a suppressor function more reliably with some guns (my interest is for a 1911 suppressor), but what is it (electrical/mechanical)?  I have heard that this will make some suppressors more costly than others, is that true?  Does anyone here run a 1911 with a suppressor, and if so, which are some good, yet cost-effective options?

Special mechanisms, called "recoil enhancers" or "Nielsen devices", are used to decouple the mass of the suppressor from the barrel. These consist of a sliding baffle in the rear of the suppressor that is forced back under the pressure of the powder gas, thus forcing the barrel backwards and unlocking the short recoil mechanism. Adding one of these mechanisms increases the complexity and cost of the suppressor.

-From Wikipedia

Isn't it the box they hook up to your t.v. to monitor what you watch for ratings?

Quoted: Isn't it the box they hook up to your t.v. to monitor what you watch for ratings?

It does sound something like that.

I did a little searching, and I have received the opinion that the AWC Nexus suppressor works well on the 1911.  Can anyone attest to the quality of this product?