Module 1	Introduction to Brake Systems
Module 2	Personal Safety Around Vehicles and Air Brake Systems
Module 3	Service Brake Chambers, Slack Adjusters and Foundation Brakes
Module 4	The Supply System
Module 5	The Service Brake System
Module 6	The Spring Brake System (Park / Emergency Brakes)
Module 7	Service and Spring Brake System Options and Design Variables
Module 8	The Tractor Protection and Trailer Supply System
Module 9	The Trailer Service Brake Control System
Module 10	Trailer Brake Systems
Module 11	Anti-lock Brake System (ABS) Basics
Module 12	Air Brake System Inspection, Maintenance and Testing

MODULE 7 Service and Spring Brake System Options and Design Variables
Secondary (Front) Service Brake Ratio / Limiter Valve (Limiting Valve)	ABI-CE 7-1 Illustration
Dry / Slippery Valve	ABI-CE 7-2 Illustration
Spring Brake System with Quick Release and       Spring Brake Valves (Inversion Valves)	ABI-CE 7-3 Illustration