Design based on "resistors series" theorem. 1/4 watt tolerance +/-1% 1206 SMD resistors. 4mm banana sockets with plugs, easy to connect wires. High quality FR4 glass fiber PCB. With spare parts 20 pieces jumper caps. This is "resistance substitution box" good low-cost alternative solution, can flexible and quick setting resistance range from 1R to 9999999R, step accuracy 1R. for educational experiments, electronic engineering design or test trimming are excellent applications. Features: Design based on “resistors series” theorem. 1/4 watt tolerance +/-1% 1206 SMD resistors. 4mm banana sockets with plugs, easy to connect wires. High quality FR4 glass fiber PCB. With spare parts 20 pieces jumper caps. Programmable Resistance: 0 to 9,999,999 ohm, 1 ohm per step. Resistance Tolerance: +/-1% Rated Power: 1/4 Watt. Max. Working Voltage: 250V. PCB Size: 89.6 x 64.2mm / 3.53" x 2.53"