These D rings are great for outfitting your Kayak Canoe or Boat
The have Stainless Steel Rings and have the following approx Measurements
Length 50mm , Width 35 mm
They come in packs of 2,4,6,8 or 10
They come supplied with fittings
Options 1 : M5 x 15 screw / M5 Nut / M5 Washer
All are A4 Marine Grade Stainless Steel - ok to use when you have good access to the NUT to tighten.
Option 2 : M5 x 15 Screw / Rubber Well Nut
This allows fitting with restricted access, the well nut also provides good waterproofing.