Which Swim cords should I get?

I am planning to get a set of cords to enhance my swim training. I am decent swimmer (mid 50’s IM)

Any input which ones to get and which resistent level: light - medium - heavy?

Thx, Axel

I’ve only ever used the Riptide, and I really like it. Plus, the owner/inventor Jim Morr is a great guy to deal with.

http://swimriptide.com/

Enjoy.

Check out Gordo’s forum (coachgordo.com). He uses swim cords often and I think this was coverered on their forum about a week or so ago. Try searching for it.