Gut string, silver wound, knot end, available in the gauges:

Gut string,  aluminium wound, ball end.

Gut string,  aluminium wound, knot end, available in the gauges:

Steel string, aluminium wound, ball or loop, in medium and heavy ball or loop.

Gut string,  aluminium wound, knot end, STIFF version. Available in the gauges:

Steel string, ball or loop. Medium only.