Cocoknits T-pins are stainless steel which means they won’t rust when they get wet during blocking. If you aren’t sure if your pins are stainless, soak them overnight in a shallow dish of water. If they rust, do not use them! 

T-pins are included in the Cocoknits Knitter's Block blocking kit, but if you need more, they are available here as a tin of 40 pins.