Actually there is/was 2 SCD grading companies.
The initial one was affiliated w/ the SCD (Sports Collectors Digest) Hobby paper and wasn't all that bad regarding accuracy.
They then sold out their "SCD" grading name, which another company called "Sports Cards Direct" which I've heard wasn't all that great.
You will see that the slabs & flips are nearly identical.
Nonetheless, the SCD grading name is confusing w/ the 2 different companies utilizing the name. Not sure if they still are operating.
Here are the 2 slabs, which I took from eBay.