You’re Stranded on a Desert Island (not dessert)

Mirror makes fire so it covers all of the signal devices, matches and fishing lures and traps so I give back fishing pole and take the knife.

My new list-

1) Water purifier (desert or for island with no moving water) since it didn't say it I am assuming it will desalinate like the one I have.
1) first aid (tropical - infection or open cuts attract insects and the warmth is breeding ground for bacteria)

2) tarp for shelter, traps and water collection.

3) mirror for reasons above

4) knife for knife stuff