Start Arrows let you use your PENPal with the CrealteLINk PRO software, free to download from MantraLingua website. 
 
Set B is the only set available at the moment. It consist of 32 stickers numbered 37-68. You do not need to start with sticker 1. More sets will be available in the future. 
 
To learn more about working with PENpal and the Sticky Laberls read this post: https://www.montenglish.com/post/penpal-a-device-which-will-change-the-way-your-students-learn