I prefer the grommet style dampers - those worm damps mute the feedback too much for my liking. Of the grommet types, I tend to select them for the specific racquet / string pattern. For an open pattern, I tend to go for something firmer. For a closed pattern, something softer.
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Pro's Pro Vibra Stop - very, very soft, squidgy, material. Doesn't provide major dampening - tends to filter the minor vibrations only. Blue is a darker royal blue rather than a lighter blue in the photos. Good if you want only minimal interference from the dampener. 2g
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Tourna Sampras 'O' damp - not too stiff, not too soft. Like baby bear's porridge, just right. Good dampener without losing feedback. Just a shame it doesn't come in different colors. 1.6g
The comments above are for the red/black ones. Tourna have recently released some white colored O rings. Exactly the same design but the white ones are MUCH stiffer than the red (softest) and black (soft).
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Babolat Custom Damp - stiffer material than the Sampras O damp, and provides a bit more dampening, firming up of the strings. Good dampener without losing too much feedback. 2g
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Pacific 'Vibra-Damper' - larger size O ring which you have to force into any denser stringing pattern. Feels quite brittle and doesn't feel like it filtering much vibration due to its brittleness. Disappointing.
