The M5 x 30W10 JIS B1188 Phil Pan Split Washer Flat Washer Sems M/S Zinc Yellow is a type of washer that is used to distribute the load of a screw or bolt over a larger surface area. It is made of steel and has a zinc yellow finish. The washer has a split design, which allows it to be easily installed and removed. It is also flat, which makes it ideal for use in applications where space is limited.