Very Effective Dampening
I have a Lite R2 with the Bredworks FR4, Boba U4T, and this silicone dampener. The thockiness is increased while minimizing the remaining hollowness of the stock case. The dampener fits without any issue and is a very easy install. Do be warned, if you're using clackier switches such as Durock L series, NK Silk, or similar, that the dampener will increase the pitch of the clack which may or may not be your preference.
This silicone pad works very well in the KBD 67 lite if your into a more muted sound signature the fit is spot on with the case this was a welcome addition to the 67 lite add ons
Definitely better than stock foam
Adds more weight, and is definitely better than the stock foam that's included with the board. Creates a slightly more muted sound that's louder, but overall I don't think the difference is that huge. Definitely recommend for silent builds.