Schwalbe Replacement Steel Spikes - Pack of 50 with Installation Tool

I recommend this product

Essential kit if you have Ice Spikers. Loose and rocky sections can rip out several spikes, so you will need this to replace them. I usually lose a few each ride. Does require muscle to get them in - press the into the hole at an angle, then straighten up.

You are supposed to do 40km on tarmac to properly set the them in - I’m not doing 40km on the road on IceSpiker tyres, which is probably contributed to why I lose a few.

It is possible to bulk buy the studs elsewhere if you know which ones to go for.

I recommend this product

Worth getting alongside the first pair of tyres so you don't need to worry about the occasional stud falling out.
Take note of the picture on the packet, you need to push the stud into the socket on the tyre tread block at an angle, then straighted the tool up and push downwards to set it into the tyre. Dead easy, and the single stud that has fallen out so far was easily replaced!
There is no need to deflate the tyre or remove it before doing this.