Klein 646-5/16M Screwdriver
- Screwdriver
- 1
- 3.2 ounces
- 9.7 × 2 × 2 inches
- Better rated than 77%
A single-purpose 5/16 inch flat driver from Klein's well-rated line, useful mainly as a specific-size addition to a set rather than a starter tool.
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How it ranks among the 158 screwdrivers we track
4.8★ across 738 Amazon ratings, Bayesian-smoothed toward the category average.
738 Amazon ratings, weighted on a log scale so huge counts don't drown everything.
100+ bought on Amazon last month.
Brand identity, imagery, description and spec coverage.
The ProductDome score is separate from the Amazon rating shown above: it combines the Bayesian-smoothed Amazon rating with evidence volume, tracked demand, and data quality across the 158 screwdrivers we track - how the scorecard works · full screwdrivers data report. Confidence: high - strong rating volume and complete data.Last refreshed Aug 4, 2026. Data-computed, not a hands-on test. Compiled by the ProductDome Research Team.
Overview
Klein's 646-5/16M ships as one fixed-tip screwdriver, carrying a 5/16 inch flat blade. It measures 9.75 x 2 x 2 inches overall and weighs 0.2 pounds, with no handle material listed in the spec sheet.
Klein numbers its cabinet-tip drivers by size, and the 5/16M code is the clearest identifier of what this tool actually does since no handle material or shank type is listed. Buying it as a single piece makes sense for filling one gap in an existing set rather than starting a collection from scratch.
- 5/16 inch flat tip
- 9.75 x 2 x 2 inch overall size
- 0.2 pound weight
- Sold as a single piece
Who it's for
Electricians or technicians who need one specific 5/16 inch flat tip to fill a gap in an existing driver set. Not a fit for someone wanting a multi-bit or starter driver, since this ships as a single fixed tip.
Strengths and trade-offs
Drawn from this product's published specifications.
- Compact at 9.75 inches overall
- Light at 0.2 pounds for a pouch
- Sold individually to match one tip size
- Single fixed tip only
- No bit-swapping or storage case
- No handle material listed
Performance notes
Shank length of 9.75 inches gives enough reach into recessed screws, while the 2 x 2 inch handle footprint keeps grip diameter modest for a single-handed turn. Weighing 0.2 pounds, it adds little bulk to a tool pouch. Because the tip size is fixed at 5/16 inch, it is a one-job driver rather than a substitute for a multi-bit set.
Specifications
| Brand | KLEIN |
|---|---|
| Model | 646-5/16M |
| Pieces | 1 |
| Item Weight | 3.2 ounces |
| Dimensions | 9.7 × 2 × 2 inches |
Other KLEIN screwdrivers
How it compares
This product against the closest alternatives we track in screwdrivers.
| Product | Amazon rating | Ratings | ProductDome score |
|---|---|---|---|
| Klein 646-5/16M ScrewdriverThis product | 4.8 / 5 | 738 | 4.3 / 5 |
| JOREST 40Pcs Small Precision Screwdriver Set with Torx Triwing PhillipsJOREST | 4.7 / 5 | 25,021 | 4.6 / 5 |
| Amartisan wwer ScrewdriverAmartisan | 4.6 / 5 | 12,513 | 4.6 / 5 |
| AXTH 25-IN-1 ScrewdriverAXTH | 4.6 / 5 | 4,763 | 4.5 / 5 |
| VESSEL 220W-3 ScrewdriverVESSEL | 4.7 / 5 | 6,242 | 4.5 / 5 |
Similar screwdrivers from other brands
Questions about the KLEIN 646-5/16M
Common buyer questions answered straight from the product spec data - no fluff, no "it depends".
What tip size does the Klein 646-5/16M use?
It carries a fixed 5/16 inch flat tip, as indicated by the model number.
Does the Klein 646-5/16M come with interchangeable bits?
No, it ships as a single fixed-tip screwdriver, one piece per package.
How much does the Klein 646-5/16M weigh?
It weighs 0.2 pounds and measures 9.75 x 2 x 2 inches overall.