A Metric Feeler Gauge Set is a compact tool consisting of multiple thin metal blades of known thickness used to measure and set small gaps and clearances. Its primary use is to check and set valve tappet clearances, spark plug gaps, bearing end-float, and other precision gaps where direct measurement with callipers is impractical.

This Draper Tools Group D metric feeler gauge set features blades manufactured from spring stainless steel (AISI 420 / EN X20Cr13) that have been hardened and tempered to retain flatness and edge stability. Blades have a satin-polished finish to reduce contamination and resist corrosion; each blade is permanently stamped with its metric thickness for easy identification. Typical blade thicknesses are supplied in incremental metric steps (for example 0.02 mm–1.00 mm) and the set conforms to standard workshop measurement practice consistent with DIN/ISO/BS dimensional tolerances for gap gauges. The blades are retained on a pivot pin with a slotted head for adjustment and folding storage, providing both rigidity during use and compact transport.

In automotive and mechanical workshops the set is widely used for setting valve clearances, ignition and distributor points gaps, and for measuring contact or shim thicknesses. It is also commonly used in general maintenance, plant engineering, HVAC, pump and gearbox servicing, and by toolroom and quality-control technicians checking mating parts and assembly fits. Because the blades are marked in metric values they are particularly suitable for European-specification engines and machinery.

Key benefits include good corrosion resistance from the stainless material, spring temper for reliable feel and repeatable measurement, and a comprehensive range of thin increments that can be combined to achieve intermediate values. The stamped identification makes rapid selection straightforward, and the folding pivot design protects blades when not in use while keeping the set compact.

Duchy Fasteners stocks metric feeler gauge sets in a variety of configurations, typically covering sizes from 0.02 mm to 1.00 mm and available in multiple blade counts (for example 12, 16 or 32-blade sets), supplied either loose or in plastic wallets to suit workshop or trade use.