KLEIN

Klein 646M Screwdriver

Screwdriver
6 inches
6.7 ounces
9.7 inches

4.8/ 5 on Amazon1,922Amazon ratings200+bought last month4.4ProductDome score

Better rated than 77%
More reviewed than 63%

High confidenceLast refreshed Aug 4, 2026Amazon data + ProductDome analysis · methodology

Best forBuy if you want a full size, brand name screwdriver for regular trade or shop use.

A standard length Klein screwdriver with a 6 inch blade capacity, suited to everyday trade use rather than tight or confined spaces.

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ProductDome scorecard

How it ranks among the 158 screwdrivers we track

4.4/ 5ProductDome scoreHigh confidence

Owner satisfaction · 56% of scorecategory median 4.7★4.8

4.8★ across 1,922 Amazon ratings, Bayesian-smoothed toward the category average.

Evidence strength · 17% of scorecategory median 1,304 ratings4.1

1,922 Amazon ratings, weighted on a log scale so huge counts don't drown everything.

Buyer demand · 11% of score3.1

200+ bought on Amazon last month.

Data quality · 11% of score3.8

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

A Klein Tools 646M screwdriver measuring 9.75 inches overall with a 6 inch blade capacity, weighing 0.42 pounds, sized for full reach into recessed screws on the job.

Klein Tools is a known name in hand tools, and the length and capacity figures here point to a full size screwdriver rather than a compact or precision driver.

9.75 inches overall length
6 inch blade capacity
0.42 pounds
Klein Tools brand

Who it's for

Fits an electrician or general tradesperson who wants a full length, standard Klein screwdriver for everyday use. Not the right pick for someone who needs a stubby or precision driver, given the 9.75 inch overall length.

Strengths and trade-offs

Drawn from this product's published specifications.

What stands out

Full 9.75 inch length reaches recessed screws
Lightweight at 0.42 pounds for repeated use

What to check first

Not suited to tight or confined spaces
Tip type and size not specified in the listing

Performance notes

The 6 inch blade capacity gives reach into recessed screws that a shorter driver cannot manage, while the 0.42 pound weight keeps it light enough for repeated use over a shift.

Specifications

Brand	KLEIN
Model	646M
Capacity	6 inches
Item Weight	6.7 ounces
Length	9.7 inches

How it compares

This product against the closest alternatives we track in screwdrivers.

Product	Amazon rating	Ratings	ProductDome score
Klein 646M ScrewdriverThis product	4.8 / 5	1,922	4.4 / 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

Frequently asked

Questions about the KLEIN 646M

Common buyer questions answered straight from the product spec data - no fluff, no "it depends".

How long is the Klein 646M screwdriver?

9.75 inches overall, with a 6 inch blade capacity.

How much does the Klein 646M weigh?

0.42 pounds.