I just re-discovered from Shure's info, the Shure Cantilever I broke so easily (it shattered after a drop of about 1", I'm still mad)
not a rod, not a tube, it was a MicrowallBe, only .0005" thick
"Trackability is the stylus' ability to stay in contact with the record groove walls at a given tracking force. The most demanding signals on a record are usually high-level, high-frequency sounds and sharp transients. Mistracking of any signal can cause record groove damage that permanently reduces future reproduction accuracy.
Trackability can be improved by increasing stylus tracking force at the expense of record and stylus tip wear.
The V15 achieves high trackability without making these sacrifices.
The V15VxMR's Micro-Ridge stylus tip and low ENGLISH effective-mass MICROWALL/Be stylus structure almost double previously achieved high frequency trackability at 10 kHz - at an optimum stylus force of only one gram!
Beryllium MICROWALL/Be Stylus Cantilever for Lowest Effective Mass Ever! Beryllium has extremely low mass and high stiffness. These properties result in superior performance, however, only when the material is geometrically optimized. The ultra-thin (0.0005-inch) beryllium MICROWALL/Be tube, shown in Figure 1c, has the lowest effective mass and highest ratio of stiffness to mass of any stylus cantilever ever, resulting in unprecedented high-frequency trackability.
Below is the Stiffness to Mass ratio for the three different types of beryllium cantilevers shown in Figure 1 (inside back cover). The physical characteristics of beryllium allow a longer length low-mass stylus structure. The resultant longer cantilever achieves the proper vertical tracking angle for a better match to the recorded signal and lower distortion"
Proper, meaning what Shure chose, 15 degrees, which is why they are named V15