The X-treme series from Sigma mobile includes exclusively feature phones from the “tanks are not afraid of dirt” category, designed for people working in extreme conditions. A typical X-treme is sealed with multiple layers of impact resistant plastic and rubber armor to protect it from dust, moisture, extreme temperatures and rough handling. Additional protective inserts, stiffening ribs and seals are located along the case, which provide increased vibration resistance, and for greater reliability, the battery can be bolted.


The IP68 rating says that the X-treme phone is protected from dust, sand, debris and water and can withstand immersion to a depth of 1.5 m for a maximum of 30 minutes. A separate emphasis is placed on the battery capacity. For example, the X-treme DT68 model has a 2100 mAh battery that is quite capacious for its dimensions, the charge of which is enough for 20 hours of talk time or 2 weeks of work without recharging. In addition to this, some members of the X-treme family support charging station mode and can transfer power to another dead gadget via an OTG adapter.

Otherwise, these are classic feature phones, made on the principle of less is more. Their capabilities are usually limited to an FM-receiver, a flashlight and a primitive camera with a resolution of 0.3 MP, as well as two SIM-card trays and a slot for a memory card. Displays are used as simple as possible and not too large to display system information and not waste battery power. The most popular formula in the series: 2.4-inch diagonal display with a resolution of 320x240 pixels.