What is the difference between a 170N and a 275N BackTow lifejacket?
The quick answer:
People often ask us if they should make their lifejacket choice based on their body weight, but in reality it is more to do with the type of sailing you are planning. For overnight sailing, offshore weekend racing, coastal passages and cruising etc the 170N will be suitable for the majority of sailors. If you are heading off to do deep ocean crossings or sailing in very cold climates, we would recommend you consider the 275N lifejacket.
In more detail:
Both sizes of jacket are ISO approved, and they both are supplied within the same cover (this means that they are both the same size) It is what is inside the lifejacket that is different:
The 170N lifejacket has a bladder inside that will inflate automatically upon submersion (unless you have a Manual jacket system, in which case you must pull the yellow toggle to inflate your lifejacket) and it will provide 170N worth of buoyancy in the water. It uses a 38g CO2 cylinder for inflation. This will turn the wearer face-up if they are floating free in the water. Is it approved for use in inshore and offshore sailing, worn in combination with foul weather clothing. It is suitable for use in all but the most severe conditions.
The 275N lifejacket has a larger bladder inside and requires a larger (60g) Co2 bottle to inflate it. It will also inflate automatically upon submersion in water. It is intended primarily for offshore use in extreme conditions. It is also useful for sailors in very cold climates where you may be wearing extra clothing that could trap air around the body and adversely affect the self-righting capability of a smaller jacket.
If you would like to check particular details with us to make sure you have the right lifejacket for you please feel free to drop us an email: firstname.lastname@example.org with some details about your sailing plans and we can help advise on the best choice.