This is the well-known beading wire from Beadalon. Their 7 strand wire is a great balance between cost and flexibility. Very strong (12 pound breaking strength) like tigertail, but a lot more flexible. This doesn't have the smooth flexibility of the 49 strand wire, but it costs a lot less!
This item is Beadalon 7 strand flexible nylon coated, stainless steel, bead string wire. Color is bright (silver), length is 30 feet, diameter is .012". Can be tied, or used with crimp beads.