4 pins solid brass lock cylinder with brass key. High security and quality level. handle square 8mm unlocking lever bolt with 6mm hole is optional single turn, 4 pins cylinder lock interchangeable: with most common rollershutter locks available on the market. The reinforced bolt makes the roller shutter more resistant toattack.reinforced steel bolt: 2mm steel platedfolded back on itself to reach overall 6.5mm thickness stright, shifted, lengthened bolt available with6mm hole solid brass cylinder rustproof zinc plated box and components 3 brass key, chromed plated item no. A b pins finish qty/box cl01.10 155 56 4 galvanized.