It sure is!
The hardware included with the Curt Lunette Ring with 5-Position Adjustable Channel - 3" Diameter - 12,000 lbs # C48640 to secure the lunette ring to the channel are 5/8" Diameter x 5-1/2" long Grade 8 hex bolts with 5/8" grade 8 washers and 5/8" grade 8 nuts.
I included a video of the # C48640 for you to take a look at. view full answer...
The Curt SecureLatch Lunette Ring with 8-Position Adjustable Channel # CU49FR does come with the hardware needed to attach the lunette ring to the channel. It is 3 bolts, 3 nuts and 6 washers. The picture below shows every piece you would receive.
If you need additional bolts you get get the Curt Channel-Mount Coupler Hardware Kit # C25388 which will come with two additional bolts and all hardware.
The bolts are 5/8" Diameter x 4-3/4" long Grade 8 hex bolts. view full answer...
The Brophy Lunette Ring w/ 5-Position Adjustable Channel Bracket # BR63ZR is most definitely a weld-on installation and you'll use those holes as a reference point during the installation. A lot of times seemingly random holes like these are what the manufacturers use to hold the product in the air during the coating process so these holes serve a dual purpose. view full answer...