The Faithfull Internal Spring Caliper is a precision measuring instrument engineered for accurate internal dimension assessments. Crafted from flat stock steel, this tool features polished natural finish legs designed for consistent performance in workshop and maintenance environments. The construction includes a robust yet flexible bow spring that maintains tension, while the centrally positioned adjustment screw allows for smooth, incremental fine-tuning of the caliper's spread. The contact points are treated to maintain durability and measurement accuracy during regular use.