The Product which you can see Beside is iPhone 6S Plus volume button flex.
iPhone 6S Plus volume button flex is a high quality and affordable repair part.
iPhone 6S Plus having problem with volume buttons Press and hold the buttons When you notice that no motion while pressing and doesn’t make proper contact with the volume button flex and its not working properly replace it with below Product.
iPhone 6S Plus volume button flex is designed to work perfectly.
The image below use to present product is just for reference
actual product will be different from image.