A tamper compacts ground coffee in an espresso basket. Its first practical requirement is a suitable fit for the basket you use. Handle shape, base construction and a stable grip then influence how comfortably you can repeat the action.
The source discusses flat and convex bases, calibrated mechanisms and a wide range of materials. Those options should not be treated as automatic solutions to uneven extraction. Distribution and a level bed still matter, and an expensive handle does not establish a measured improvement in the espresso.
Confirm the required diameter and check that the tool can be cleaned easily. Try the grip if possible, particularly if you prepare many shots. Develop a consistent, level routine rather than trying to compensate for other problems with increasing force. When comparing tools, keep the coffee dose and basket constant. The worthwhile result is a tamper that fits your equipment and makes careful preparation easier to reproduce.
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