What rim dimensions can this tool measure? The tool measures Nipple Seat Diameter (NSD) directly and can also be used to determine Effective Rim Diameter (ERD) when required using supplied short reference spoke nipples. This allows builders to choose the correct reference depending on rim and nipple design. When should I use NSD instead of ERD? NSD is recommended for modern carbon rims, deep nipple heads, or performance spokes where small geometric differences matter. ERD remains useful when calculators or legacy data require the final spoke end position. Can I measure carbon rims with angled drilling? Yes. The probe design allows stable seating even on rims with slightly angled spoke holes and deeper cross-sections, provided access holes allow probe insertion. For deep section wheels, there is an additional pair of probes available as an accessory. What rim sizes are supported? Modern rims up to 32″, with a maximum of around 90 mm external width, and access holes large enough for probe insertion. Does the tool work with different nipple types and lengths? Yes. Note however, that the probes measure head-to-head distance. When using longer nipples, DSN nipples, or hex-head designs, the builder must apply a known deduction since spoke ends before reaching spoke nipple's end. This is explained in the manual and in the NSD article. How accurate are the measurements? The digital gauge provides repeatable, high-resolution readings suitable for professional spoke length calculations. Accuracy depends on correct probe / nipple seating and zeroing, as described in the manual. Is this tool compatible with SpokeCalc? Absolutely. Spoke calculator inside the App SpokeCalc supports both ERD and NSD-based workflows, including defined nipple geometry. Measured values can also be stored as rim components for future reference. Even if you do not use the SpokeCalc, you can easily derive ERD from measured NSD using reference Spoke nipple data table, enclosed with the tool.