Sigma ROX 4.0 GPS Bike Computer - 25-Hour Battery

Sigma ROX 4.0 is a compact GPS bike computer with a 2.4-inch transflective display, a barometric altitude sensor, and navigation support. The unit weighs 51 g and uses a rechargeable 550 mAh, 3.7 V battery.Sigma's ROX 4.0 specifications place it in the compact GPS cycling computer category, with physical buttons rather than a touchscreen.

Display And Navigation

The screen measures 2.4 inches and uses transflective technology with a 59 by 23 pixel main display. Sigma lists two display colors, GPS and GLONASS reception, and more than 30 functions for riding data and navigation.

Route planning takes place through a connected smartphone and the SIGMA RIDE app. The computer can show navigation information, altitude, inclines, declines, speed, distance, and training time. It does not provide a full map view, so the navigation experience centers on route guidance and ride data rather than an on-device map.

Battery And Sensor Support

Sigma rates the rechargeable battery for up to 25 hours of typical use. The 550 mAh cell operates at 3.7 V, while ANT+ and Bluetooth Low Energy provide links for compatible sensors and a smartphone.

The computer supports speed, cadence, and heart-rate sensors, along with SIGMA's remote control and compatible e-bike data. The standard package is distinct from sensor bundles, which can add equipment and change the price.

Weatherproof Construction

The ROX 4.0 carries an IPX7 water-resistance rating and an operating temperature range of 0 C to 60 C.The short manual also lists GPS at 1575.42 MHz, GLONASS at 1602 MHz, and transmission power below 4 dBm.

Its dimensions are 44.9 by 73.6 by 18.4 mm, and the listed mounts include the GPS Mount and Overclamp Butler. The Overclamp Butler fits handlebars from 31.8 to 35 mm in the cited product information.

Position In The Category

The ROX 4.0 sits below newer Endurance versions in battery life, with the standard model rated at 25 hours while the ROX 4.0 Endurance is listed at 41 hours. The standard unit therefore suits riders who want GPS, sensor connectivity, and navigation data without a touchscreen or full map display.

A listed US retail price was $68.99 as of 09/07/2026.That price places the base computer near the lower end of dedicated GPS bike computers. The strongest fit is for cyclists who value a light head unit, long stated runtime, ANT+ and Bluetooth support, and turn-by-turn guidance from a phone-connected route.