With the advent of smart bicycle helmets, a two-way radio capability has become available to cyclists. This addition can bring peace of mind and enhanced safety when cycling on roads or trails with high traffic. But before investing in such technology, it is important to understand what kind of radio frequencies are used by these two-way radios. Radio frequency (RF) signals are measured in Hertz (Hz). The lower the Hertz number, the longer the wavelength - and conversely, higher numbers indicate shorter wavelengths. For example, an FM broadcast station operates at about 100MHz (megahertz), which equates to a very short wave length RF signal. Bluetooth devices generally operate at 2.4GHz, whereas Wi-Fi devices operate from 5 GHz up to 6 GHz depending upon the network type. Smart bicycle helmet manufacturers may use any combination of these frequencies for their two-way communications capabilities, depending upon the brand and model chosen. It is recommended that cyclists do some research online prior to purchasing a new helmet to ensure compatibility with other electronics they might be using while riding their bike. Additionally, many models offer additional features such as cell phone or GPS integration that could significantly enhance safety measures while on a ride. All this information should be readily accessible through product descriptions or user manuals provided by each manufacturer.