The Karoo Sand Snake is mildly venomous and holds no threat to humans. There are various other sand snakes which can cause some confusion.
Sources:
(*) https://www.africansnakebiteinstitute.com/snake/karoo-sand-snake/
(*) https://www.tyroneping.co.za/snakes-southern-africa/psammophis-notostictus-karoo-sand-snake/
Slang
They can reach a length of up to 1m and is a fast moving snake. They are active in the day and feeds on lizards, skinks and rodents. In some areas they are quite common.
Sources:
(*) https://www.africansnakebiteinstitute.com/snake/karoo-sand-snake/
(*) https://www.tyroneping.co.za/snakes-southern-africa/psammophis-notostictus-karoo-sand-snake/