Yoshimi is a metal manufacturer specialized in shape memory alloy. This wire is made of shape memory alloy and it is very flexible. Made in Japan.

Shimkei-jime wire is to paralyze fish body to keep fresh meet longer, to prevent fish meat getting hard. You make a hole with a pick to the head of games and then insert this wire toward center of spine, and spinal cord will be destroyed and fish will not move any more.

0.6mm is for flat head, for which spinal cord hole is small. 0.8mm is for all round, like yellow tail from 1kg to 10kg.

I recommend you to attach a float like lure to this wire and you may easily find it in bags, and it will float when you drop it in water.