I really like being able to secure my lines when I wrap up after a session and the lack of bar-end bungees on my Slingshot bars was getting me down. The 2013 Slingy bar has little Velcro "Line fixers" at the "Oh Shit" handles, but I found them cumbersome when it's really windy and/or my fingers are cold.
So I spent about about 5 minutes to cut two 15" pieces of small diameter bungeee, melt the ends and tie them on.
Loosey Goosey Lines:
Tie a square knot, just under the floats:
Tie an overhand in the end:
Mucho Bueno: