The three most popular Trulock choke constrictions for sporting Clays are skeet 1, skeet 2 (lite mod) and imp mod. These constrictions generally work well on any Sporting Clay or 5-stand course.
Skeet – Just slightly tighter than cylinder bore, skeet choke tubes are made to get a quick spread on shot while providing slightly more range. Ideal for the close shots common on a skeet range or when shooting other clays.
https://chokefortrap.com/best-choke-for-sporting-clays/
1 notch = Full. 2 notches = Improved modified. 3 notches = Modified. 4 notches = Improved cylinder. 5 notches = Cylinder.