Curve of the U-bolt is flattened, or "coined", to reduce impact on boat material. It's shaped to fit our 1 5/8" frame pipe.
The 2 1/8" deep Standard size U-bolt is used with LoPro Frame Fittings.
We use the longer 2 1/2" deep Oversized U-bolt with our Raft and Cataraft Anchor Systems, Lower Cat Rail Spreader Bars and Cataraft Frame Aluminum Floors. Folks building their own custom frames may also find use for these U-bolts.
Each U-bolt comes with two 1/2" zinc-coated nylon-locknuts and two zinc-coated flat washers.