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  1. Home
  2. /Running Shoes
  3. /Nike
  4. /Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB
Running ShoesNike

Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB

6.0

VersusMatrix

out of 10

310g
Weight

Where to Buy

ebay

from $65

Buy →

amazon

from $65

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Prices may vary · We may earn a commission. Learn more

Score Breakdown

PricePricePerformancePerformanceBatteryBattery
Price
9.8
Performance
3.5
Battery
3.5

Why is Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB better than average?

+18%

Price

$65 vs avg $79

Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB — Full Specifications

Price (USD)
$65

See a missing or incorrect spec? Let us know

About the Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB

The Nike Men's Flex 2021 RN Running Shoes in Black, White, and Smoke Grey are designed to provide a comfortable and versatile running experience. Released in 2026, these shoes feature a sleek and modern design that effortlessly blends style with functionality. The breathable mesh upper ensures optimal ventilation, while the supportive overlays provide a secure fit. The neutral color palette makes them a versatile choice for both casual wear and athletic activities.

Performance-wise, the Flex 2021 RN is engineered for flexibility and comfort. The lightweight foam midsole delivers responsive cushioning, allowing for a smooth ride on various surfaces. The rubber outsole offers reliable traction, making these shoes suitable for both road running and light trail use. However, some users may find that the overall support could be improved, as the shoe tends to lack the stability needed for longer distances.

Key features include a padded collar for added comfort, a pull tab for easy on and off, and a flexible design that promotes natural foot movement. While the Nike Men's Flex 2021 RN Running Shoes score a modest 6 out of 10 overall, they remain a solid option for casual runners or those seeking a stylish everyday shoe.

Who Should Buy This?

The Nike Men's Flex 2021 RN Running Shoes are perfect for casual runners, fitness enthusiasts, and those seeking comfortable everyday footwear. Ideal for students and professionals who value style and comfort during their busy days, these shoes excel in price but may fall short in performance for serious athletes or long-distance runners. While they offer a sleek design and decent cushioning, buyers should note that they may not provide the advanced support needed for high-intensity workouts or prolonged wear.

Reviewed by VersusMatrix Editorial Team

Last updated: April 13, 2026

Editorial guidelines

Methodology: AI-powered analysis of technical specifications from manufacturer data. Scores are calculated by comparing products across multiple dimensions and normalized relative to the full category database. Our editorial process is independent and not influenced by affiliate partnerships.

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Frequently Asked Questions

Is the Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB worth buying in 2026?

The Nike Men's Flex 2021 RN Running Shoes in Black, White, and Smoke Grey are designed to provide a comfortable and versatile running experience. Released in 2026, these shoes feature a sleek and modern design that effortlessly blends style with functionality. The breathable mesh upper ensures optim...

What is the price of the Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB?

The Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB is priced at approximately $65. Check the buy links above for current prices from retailers.

Who should buy the Nike Men's Flex 2021 RN Running Shoes Black White Smoke Grey Size 9.5 NIB?

The Nike Men's Flex 2021 RN Running Shoes are perfect for casual runners, fitness enthusiasts, and those seeking comfortable everyday footwear. Ideal for students and professionals who value style and comfort during their busy days, these shoes excel in price but may fall short in performance for serious athletes or long-distance runners. While they offer a sleek design and decent cushioning, buyers should note that they may not provide the advanced support needed for high-intensity workouts or prolonged wear.

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VersusMatrix Score

6.0

out of 10

$ Price
40%9.8
Performance
35%3.5
Battery
25%3.5

How We Score

Scores are calculated by comparing all running shoes in our database. Each dimension is weighted and normalized relative to the category.

$ Price40%

Based on Price (USD) · lower is better

Performance35%

Based on Benchmark Score

Battery25%

Based on Battery Life (hrs)

Products missing data for a dimension receive the median score. Overall = weighted sum of all dimensions.

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