Grill or griddle???
As noted, the 17 and 22 inch models have an external regulator that accepts a 1 lb propane bottle, and quick screw connects to griddle fitting. Thus the griddle is LOW pressure.
90 degree adapters, (hose is out of the way)
Straight adapters (hose gets in the way)
Hose and 90 fitting as a combo
I highly advise against getting a hose with a permanently attached fitting for the griddle (they are readily available) because it restricts the use of the hose to this one item. Get a hose with a male nipple and a female coupling and shutoff valve, 12 to 15 ft long.
If the coupling you are looking at has criss cross or diamond patterened knurling that is for the Blackstone, if it has numerous straight grooves cut length wise around the fitting then it is larger and fits some of the Coleman models but not the Blackstone.
To add to this, head to Wal-Mart and go to the garden section where the grills are. This is fall, when the stuff gets clearanced. They do not restock anything, it gets sold for some price. I bought my 17 inch for $54 in 2018 when they were regular priced at about $75. If they have not marked it down, they will, just keep checking back, check several stores. Much better than ordering it and paying full price. You will find a bunch of other stuff marked down too, so you can stock up on aluminum cups for the grease trap, cooking utensil kits, metal domes for heating/melting. Get a pair of Cuisinart outdoor grill shears/scissors. They are very well made and eliminate the need for steak knives, just pass the shears around the table and cut your steak up.