Dyneema, Spectra and Amsteel Blue are all similar ropes made of ultra high molecular weight polyethylene, generally 12 stranded. It is light and easy to splice, very strong and abrasion resistance.
Every sailboat should have a supply handy. Besides being a backup for failure of standing rigging etc, it is convenient to use for making lightweight, soft shackles. A great place to begin learning about how to make these is found HERE.
A Whoopie Sling One great variation here is to put a soft shackle at one end. David Samuelsson made one of these for Villa G which we use to hold the boom in place when at anchor. We simple attach the end with the eye on a padeye using a girth hitch and the soft shackle end goes onto one of the blocks on the boom.
