Throw lines are a really important bit of safety equipment. They can be stored easily without the rope getting tangled and be ready for use. Most Ajax and Warspite throw lines are between 15m & 20m
There is a really good article here with hints and tips: https://palmequipmenteurope.com/blog/2018/08/20/throwline-top-tips-101/
The RNLI’s guide of how to use your throw bag: https://rnli.org/magazine/magazine-featured-list/2016/june/how-to-throw-a-line
Of course, repacking it is important: .
An example of throwlines in use:
Want to know more?
Here is a manual from another maker: https://safequip.co.uk/wp-content/uploads/2017/12/PCU015-IONIC-Throwline-User-Manual-v1.pdf; This is more in depth but it is a great resource to take a read through.