Must have tools for SEN Support Staff?

I am starting a new school as an SEN support assistant working across multiple classrooms. My role involves supporting individual students with additional needs 45 minute sessions. I will be moving around a lot, and I want to make sure my bag is stocked with all the essentials to support my students and stay organised. So far, I’ve got a planner, battery pack, and pens/pencils - but I’m wondering what else might be useful. Would love to hear what others keep in their bags when working across classes. Any suggestions or must haves?