Quick take
When you are outfitting a dimensional metrology machine inspection station, the core decision is whether you need a readout display for an optical measuring microscope or a hand-held digital caliper for direct part measurement. This group includes one used Nikon MC-102 2-axis digital readout and three new digital calipers with 6-inch, 8-inch, and 12-inch maximum measurements. Listed prices run from $45.00 for the 6-inch caliper to $153.30 for the 8-inch model with output; the 12-inch caliper is listed at $89.10. If you already have a measuring microscope or optical comparator, the DRO fills a different seat on the bench. For hand-held checks, the real question is measurement range and whether you need data output.
Listed-price comparison
The bars show where each listed price falls within this four-product range.
| Product | Listed price | Price bar |
|---|---|---|
| Nikon MC-102 DRO | USD 140.00 | |
| 12-inch Absolute Digital Caliper (500-193-30) | USD 89.10 | |
| 6-inch Absolute Digital Caliper (500-196-30) | USD 45.00 | |
| 8-inch AOS ABS with Output (500-172-30) | USD 153.30 |
Decision matrix
If your part sizes fit a certain range, start here.
| If you need... | Start with... | Why it fits |
|---|---|---|
| A readout for a measuring microscope or optical comparator | Nikon MC-102 DRO | Used 2-axis display shows X/Y coordinates from linear encoders |
| Up to 12 inches of measuring range from a digital caliper | 500-193-30 12-inch model | 0-12 in span plus Absolute encoder convenience |
| A small everyday caliper at a lower listed price | 500-196-30 6-inch model | 0-6 in span, dual-unit conversion, no SPC output |
| An 8-inch hand-held caliper with output and clear MPN/UPC | 500-172-30 8-inch model | 8 in/200 mm span plus AOS ABS with output |
Product notes
Nikon MC-102 Digital ReadOut Unit DRO
The Nikon MC-102 is the only non-caliper here. This used 2-axis digital readout unit is typically paired with Nikon measuring microscopes and optical inspection equipment, and it interprets linear encoder signals to show real-time numeric X/Y coordinates. It is not the lowest listed price in this group, but it fills a completely different role: a display unit rather than a hand-held tool. If you already have a microscope or optical comparator and you need a readout, this is the product to consider. The limitations are plain: it is used condition, the power cord is not included, and it is not a replacement for a caliper when you need direct physical measurements.
12-Inch Absolute Digital Caliper (500-193-30)
This new digital caliper spans 0 to 12 in and sits in the middle of the listed price range. The description highlights ±0.02mm (±0.001") accuracy, an Absolute encoder that avoids origin resetting, a digital LCD, stainless steel construction, metric/inch conversion, and a data output port for SPC transfer. That mix makes it the longest-range hand-held option in the set. The trade-off is reach and cost compared with the 6-inch model: if most of your parts are smaller, the 6-inch caliper covers that work at a lower listed price. If you are measuring 12-inch work and want absolute measurement convenience, this one is worth matching to the job.
6-Inch Absolute Digital Caliper (500-196-30)
At the lowest listed price in this group, this new caliper measures 0 to 6 in and comes from Japan. The listing notes a resolution of 0.01mm / 0.0005" / 1/128", metric/imperial conversion, zero/ABS functions, and a large LCD. The practical limit is the no-SPC-output detail: this is a direct-reading caliper, not a data-export tool. The 6-inch maximum also means larger parts need one of the longer-range models. If your inspection routine stays under six inches and you do not need data output, this option leaves the most room in the budget.
8-Inch AOS ABS Digital Caliper with Output (500-172-30)
This is the top listed price in the set. It is a new 8-inch/200 mm digital caliper with MPN 500-172-30, UPC 603908579427, and the title flags AOS ABS with Output. For an 8-inch reach plus data-output capability, it fills the ground between the 6-inch and 12-inch models. The limitation is the listed price: it is the most expensive of the four, so if you do not need output or your parts fit within the 6-inch span, you can meet the measurement requirement at a lower listed price. Choose it when the 8-inch range and output capability are both requirements.
Final recommendation by use case
- Need a readout for a Nikon measuring microscope or optical comparator? The used Nikon MC-102 DRO is the relevant choice, but plan for the missing power cord.
- Need 12-inch hand-held measuring range? The 500-193-30 is the longest-span caliper here.
- Need a compact everyday caliper at a lower listed price? The 500-196-30 6-inch model handles small parts without SPC output.
- Need 8-inch range plus output with clear MPN/UPC? The 500-172-30 is the model to pick.
In short, match the maximum measurement to your largest regular part, then decide whether data output and a readout are worth the price difference.
