Dritz Glass Head Pins are heat-resistant and can be ironed over without damaging fabric. These pins are designed to pierce through delicate fabrics and are great for machine piecing. Nickel-plated steel Heat-resistant glass heads Ultra-fine shaft Nickel-plated steel Reusable plastic storage box with curved side for easy pin removal Size 22 (1-3/8") Nickel-Plated steel Glass Head Pins, 150 Ct.