These are the 100mm lenght ones that can be cut down to the required size. Sold in packs of approx. 40, they are copper coated with a spearhead. Warning these are sharp pointed things, beware of your hands. (now in 40s and not the 80s as before)
The latest stock are the old slightly thinner versions with the copper coating, they will replace the current stock. Nothing to do with us, the suppliers have just managed to get the wire they previously used I presume.(15 12 2020)