The Hipshot Tremsetter
is a piston/spring device that installs in place/lieu of (typically) the middle spring of your trem. It also involves replacing the spring-claw with the pieces provided - two single hooks go onto the screws (or an optional two-hook onto one screw if you need three springs along with the Tremsetter), which are put back in as they were, each supporting one (or two_ springs each. The Tremsetter is anchored with a hook which screws into the bottom of the spring cavity
- detailed instructions on how/where to place this are included, along with the typical trimming of the center rod of the Tremsetter.
The other end of the Tremsetter hooks into the trem block as any other spring would.
There is a single Allen bolt adjustment which has to be set to determine the coarse adjustment of the device.
The piston/spring has an adjusing barrel screw which can add/relieve the tension on the spring for the finer adjustment - this allows you to determine how much the device resists movement, holding instead at the 'zero' position, where contact is maintained for true return-to-neutral positioning.
It has to be set quite radically strong in order to lock out the bending/pulling flat effect that you mention; this is all dependend upon string guage and all of those sorts of factors that always figure into trem action.
Anyway, it's quite easy to install - but you have to know that there's one hole to be drilled for the anchor piece. And you'd need a wire-cutter or similar to trim the central rod (if necessary) to the correct length for your trem cavity.
I have one; tried it out, and found that it interfered enough with the subtlety of the trem that I pulled it out. However, I have often recommended these things to those who mention things like the country-type bending effect, as well as those who have trems that, for one reason or another, will not return properly to a neutral position - this thing will fix that by forcing the issue.
Hope this helps. =]