Hope you also have (in order of priority, at least mine) mobile phone, DSC VHF, EPIRB/PLB.
Last season I had to seek outside assistance for the first time in over 40 years. Not life threatening, but picked up a string of pots when I ran over a floating line under sail, well clear of the marker. Tethered to the seabed with the rope around the keel. About 1 mile SE of East Looe channel coming out of Poole. Fortunately a day like today with just a slight swell. VHF call to Solent coastguard to explain the position and 45 minutes later the big RNLI RIB with 6 crew arrived. One went over the side and traced where the rope went. RIB pulled my boat back to create some slack, cut the pot rope, pulled it free and rejoined it and I was on my way.
BTW if you ever do need to call for help, coastguard want Lat/Long for position, RNLI prefer bearings to or from a known point (in my case would have been my waypoint for East Looe outer buoy) but helicopters work to ordnance survey co-ordinates for coastal work. Not that you are likely to need to speak directly to the chopper with a position.