This D-ring is an OEM replacement and may be slightly bigger the original. It measures 3.25 inches in diameter. It does not come with glue!  We recommend using HH-66 vinyl cement glue available through Amazon.com. 
Replacing a broken D-ring is easy! 
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Mask off the work area around the D-ring well.
 
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Use a little acetone or basic paint thinner to get the old material off.  A green scrub pad helps to get the old glue off and will make the SUP material a little tacky and discolored-but that's what you want for good adhesion of the new glue.
 
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Spread some of the HH-66 glue on the D-ring patch and position in place. Use some tape to hold it in place while it dries.
 
- It takes 48 hours for the glue to cure, and then you can tie the bungee back on and be good as new!