Wieland fuse terminal blocks wkfn 4 fsi with spring clamp wieland 5670440550 this fuse terminal block wkfn 4 fsi with spring clamp from wieland is for mounting on a ts35 din rail top hat rail featuring a 400v rated voltage and 11mm wire strip length along with a 013 6mmsup2 minimum cross section solid and 013 4mmsup2 minimum cross section fine stranded wieland 5670440550 fasis fused disconnect din block wkfn 4 tkg35 grey