Each piece is 2cm wide! We often deliver them at 4cm, so please cut them in half to 2cm and apply. [52cm, Primary Color Lavender] Merit Hair: This is our original seal extension, a perfect blend of high-quality Japanese-made artificial hair and the finest human hair. Regarding Merit Hair: You can use curling irons and flat irons without issue. It's very close in quality to human hair, so you can rest assured. Over 90% of Remy hair on the market is hybrid. The quality of Remy and hybrid hair is exactly the same, making it impossible even for professionals to tell the difference, so please be careful not to be deceived. Even with artificial hair, the quality can be quite poor if it's made in China. Please be aware of this as well. We receive many complaints that the color is different from the photos, or that it's lighter or darker than expected. Due to the nature of seal extensions, the appearance changes depending on the time of day, the lighting, and the individual. Please purchase at your own risk, as there are individual differences in quality. Occasionally, buyers demand unreasonable returns, but we will not accommodate them. (Please be especially careful if you are buying impulsively during the high season.) Especially, there are people who try to threaten us by changing the number of extensions and claiming the color is different from what they expected, but please confirm that you are purchasing at your own risk.