Description
Condition
Used (Excellent Condition / Incomplete Set). This pin gauge set is in excellent used condition. The pins themselves look pristine, with the steel surfaces appearing perfect and free from corrosion or handling marks—”like new.” Set Status: This is a partial set. The standard PG-1 series contains 190 pins; I have identified that the 3.425mm pin is missing.
Product Overview
The SK (Niigata Seiki) PG-1 is a precision steel pin gauge set designed for high-accuracy bore measurement. Unlike standard sets that step in 0.1mm or 0.01mm increments, the PG series features a 0.025mm step.
This fine increment allows you to determine the exact size of a hole with much higher resolution. For example, if a 3.00mm pin fits loose but a 3.025mm pin doesn’t enter, you know the hole is exactly between those sizes. The pins are 50mm long, providing ample reach for checking straightness or depth. They are hardened to HV650 or more to resist wear and are sub-zero treated to prevent dimensional changes over time.
Brand Information
Niigata Seiki (SK) is a premier Japanese measuring tool manufacturer. Their pin gauges are the industry standard in Japan for quality control, known for their perfect cylindrical grinding and consistent hardness.
Specifications
| Feature | Specification |
| Brand | SK (Niigata Seiki) |
| Model | PG-1 Series |
| Range | 1.550mm – 6.275mm |
| Step (Increment) | 0.025mm |
| Length | 50mm |
| Total Pins Included | 190 |
| Material | Hardened Gauge Steel (HV650+) |
| Missing Pin | 3.425mm (Confirmed) |
Keywords
SK Niigata Seiki, PG-1, pin gauge set, 0.025mm step, bore sizing, plug gauges, Japanese tools, precision measuring, 1.55-6.275mm.
