What's in your peds OT bag

I'm a peds therapist working at a large (aka hectic) clinic and I always have a hard time finding what I need when I need it, so I'm making my own bag of simple activities to help streamline sessions.

What are everyone's favorite OT toys?

I work with mostly 3-6 year olds, so looking for that age range acts. Also looking for a durable bag to keep my toys safe and contained.