What is the D-ring for?

[SUPlakes]

My friends just got inflatable SUPs and both have D-ring attached to the bottom front.  I would think they'd create drag.  What function do they serve?

[DavidJohn]

I think they're there for towing and I don't think drag is much of an issue.

[PonoBill]

Towing rings are really handy. A number of SUPs had leash plugs under the nose in the early days. My Starboard 12'2" has one. Came in very handy when I had two friends visiting Maui and only two Hobie Adventure Islands. I ran a rope to the board, one of my friends laid on it while the other sailed the second AI, and I towed my buddy all the way to Molokini to snorkel and back to Kihei. When we got back my friend was asleep lying on the board.

[SUPlakes]

Thanks, that makes sense about towing.

Towing rings are really handy. A number of SUPs had leash plugs under the nose in the early days. My Starboard 12'2" has one. Came in very handy when I had two friends visiting Maui and only two Hobie Adventure Islands. I ran a rope to the board, one of my friends laid on it while the other sailed the second AI, and I towed my buddy all the way to Molokini to snorkel and back to Kihei. When we got back my friend was asleep lying on the board.

Sounds like an awesome trip, although I would have wanted to stay awake for the whole thing

[robcasey]

The 2015 Imagine boards had a D-ring on the bottom nose to hide the back end of the pump valve on the deck. But it did work as a great tow line attachment or nose tie-down on the car. Mine ripped off at some point. 

For the tail D-rings on deck for the leash, I just attach the leash to the big ol' handle there.