- Window sensor for invisible fixation inside window frames\n- Reliable detection by magnet/reed contact sensor technology\n- Slim design fits into most DIN window frames\n- No optical disturbance on wooden or coloured window frames\n- Reliable detection of unauthorized opening of tilted windows\n- Battery operated (2 x CR2354 button cells, included)\n- Low battery warning at the base unit\n- Fixation material included