MXR DC Brick M237 Multi-Power Supply for Effect Pedals Guitarist with an extensive collection of pedals will always need to supply safe and stable power. Power failure due to dead batteries can ruin a performance and take away from your tone. The MXR M237 power brick provides up to 8 x 9 Volt pedals and 2 x 18 Volt pedals. The FCLC protection circuit protects your valuable effects against over voltage and short circuits. Red LEDS warn for shorted pedals. Power adapter and connecting cables included.