whistle & reflective mirror
At one of the basic kayak classes I attended a refelctive mirror & whistle were recommended (now in the pocket and tied to the vest). Also in or on the kayak I have flares, a paddle float, and a spare paddle. I think I may get a refresher on how to use these things though so I’m not trying to remember/figure it out in an emergency. Not much good to bring all this stuff if by the time you need to you don’t know how to use them.
not much
whistle, radio, some paracord and a pair of carabiners in one pocket, crkt bear class blunt tipped serrated in safety orange.
first aid kit, dry clothes, firestarter in the boat.