Paddle Floats
Paddle floats are flotation devices that attach to the blades of a paddle with a bungee cord or buckle. These are of use when using your paddle as an outrigger to get back into your kayak after a wet exit.
Bilge Pumps
Bilge pumps are used to pump water out of the cockpit once you have righted your kayak after capsizing. These are made out of hard plastic and are approximately 12 to 18 inches long. They should also have a foam float so you won't lose them when capsizing. These make clearing water from your kayak go a lot faster.
PFD (Personal Flotation Device)
This is a critical piece of gear and should be worn at all times on the water. Choose a type 3 or 5 PFD as recommended by the Coast Guard. Most are made of closed cell foam and come in a variety colors, though a bright color such as red or yellow is best. These should fit snugly so that if someone were to pull up on the shoulders it doesn't slip. Attach a whistle to your pfd if it doesn't already come with one.
Tow Rope
These are made specifically for kayaking. Should a kayaker become hurt or unable to paddle, another kayaker in the group can tow that person and their kayak using a tow rope.
Hatch Floats
Every kayak should have a hatch float in the bow and the stern, even on day trips. Hatch floats prevent the kayak from taking on water, which could sink the boat should a hatch seal come loose or completely off in rough waters.
Marine Band Radio
If traveling on open water, you must have a marine radio and know how to use it. Carry it in a small waterproof case. Be aware that although many cases claim to be waterproof, they are not completely waterproof in salt water.