The WAGO relay, which is very compact, with only 6mm wide relay, is easy to maintain with the terminal. Such small gauges save space on the panel, they can switch currents up to 5A, there is one single contact. There are also new generation universal relays that can only operate from continuous and alternating voltage from 24 to 240V. The 857 series can be replaced with new ones if it has failed, the 859 relay design is still smaller, but the relay itself is lit. Various colored vests can be used for fast and reliable work, especially the 857 series is flexible. As with all other WAGO products, a spring is used to connect the contacts, and therefore relays work reliably with high temperature variations, vibrations.