Color coded for fuse actuation current type “D”.

SPOLET COLOR
Pink NOMINAL CURRENT (In) 2A
Brown NOMINAL CURRENT (In) 4A
Green CURRENT CURRENT (In) 6A
Red NOMINAL CURRENT (In) 10A
Gray CURRENT CURRENT (In) 16A
Blue NOMINAL CURRENT (In) 20A
Yellow NOMINAL CURRENT (In) 25A
Black NOMINAL CURRENT (In) 35A
White NOMINAL CURRENT (In) 50A
Orange NOMINAL CURRENT (In) 63A

This fuse acts in conjunction with a (very thin) wire connected in parallel with the fuse link which when melting detaches the fuse indicating the blown fuse, has a specific color representing the value of the fuse rated current as indicated above.