the item you’re installing weighs 57 pounds or less, an A5 anchor is suitable, which works with a #8 sheet metal screw. An A6 anchor holds 69 pounds, while an A8 can manage 85 pounds.
1 7/8" Spacing between Mounting Bolts
.2178" x 1-7/8" Shaft, with Flat
looks to be definitional part that fits our model