OS1st AC4 Active Comfort Socks - No Show
Product Details
Overview:
The OS1st AC4 Active Comfort Socks - No Show are built with two of OS1st's signature technologies, a nano-bamboo charcoal cushion and OS1st’s cooling Skin Thin™ Technology for temperature regulation for the ultimate comfort experience! These socks feature blister protection, contoured padding, and a light... read more
OS1st AC4 Active Comfort Socks - No Show - Black / Small: Men's 4-6 / Women's 4-6.5 is backordered and will ship as soon as it is back in stock.
Men's Size Conversions
| U.S. SIZE | EURO SIZE | UK SIZE | INCHES | CM |
| 6 | 39 | 5.5 | 9 1/3" | 23 3/4 cm |
| 6.5 | 39 | 6 | 9 1/2" | 24 1/10 cm |
| 7 | 40 | 6.5 | 9 2/3" | 24 1/2 cm |
| 7.5 | 40-41 | 7 | 9 5/6" | 25 cm |
| 8 | 41 | 7.5 | 10" | 25 2/5 cm |
| 8.5 | 41-42 | 8 | 10 1/6" | 25 4/5 cm |
| 9 | 42 | 8.5 | 10 1/3" | 26 1/4 cm |
| 9.5 | 42-43 | 9 | 10 1/2" | 26 7/10 cm |
| 10 | 43 | 9.5 | 10 2/3" | 27 cm |
| 10.5 | 43-44 | 10 | 10 5/6" | 27 1/2 cm |
| 11 | 44 | 10.5 | 11" | 28 cm |
| 11.5 | 44-45 | 11 | 11 1/6" | 28 2/5 cm |
| 12 | 45 | 11.5 | 11 1/3" | 28 4/5 cm |
| 13 | 46 | 12.5 | 11 1/2" | 29 1/5 cm |
| 14 | 47 | 13.5 | 11 2/3" | 29 3/5 cm |
| 15 | 48 | 14.5 | 11 5/6" | 30 cm |
| 16 | 49 | 15.5 | 12" | 30 1/2 cm |
Women's Size Conversions
| U.S. SIZE | EURO SIZE | UK SIZE | INCHES | CM |
| 4 | 35 | 2 | 8 1/3" | 20 1/5 cm |
| 4.5 | 35-36 | 2.5 | 8 1/2" | 21 3/5 cm |
| 5 | 36 | 3 | 8 2/3" | 22 cm |
| 5.5 | 36-37 | 3.5 | 8 3/4" | 22 1/4 cm |
| 6 | 37 | 4 | 9" | 22 4/5 cm |
| 6.5 | 37-38 | 4.5 | 9 1/6" | 23 cm |
| 7 | 38 | 5 | 9 1/3" | 23 3/4 cm |
| 7.5 | 38-39 | 5.5 | 9 1/2" | 24 1/10 cm |
| 8 | 39 | 6 | 9 2/3" | 24 1/2 cm |
| 8.5 | 39-40 | 6.5 | 9 5/6" | 25 cm |
| 9 | 40 | 7 | 10" | 25 2/5 cm |
| 9.5 | 40-41 | 7.5 | 10 1/6" | 26 cm |
| 10 | 41 | 8 | 10 1/3" | 26 4/5 cm |
| 10.5 | 41-42 | 9 | 10 1/2" | 26 3/5 cm |
| 11 | 42 | 9.5 | 10 2/3" | 27 1/10 cm |
| 11.5 | 42-43 | 10 | 10 5/6" | 27 1/2 cm |
| 12 | 43 | 10.5 | 11" | 28 cm |
Children's & Youth Size Conversions
Children's Size Conversions
| U.S. SIZE | EURO SIZE | UK SIZE | INCHES | CM |
| 5.5 | 21 | 4.5 | 5 1/6" | 13 1/10 cm |
| 6 | 22 | 5 | 5 1/4" | 13 1/3 cm |
| 6.5 | 22 | 5.5 | 5 5/12" | 13 3/4 cm |
| 7 | 23 | 6 | 5 7/12" | 14 1/5 cm |
| 7.5 | 23 | 6.5 | 5 3/4" | 14 3/5 cm |
| 8 | 24 | 7 | 5 11/12" | 15 cm |
| 8.5 | 25 | 7.5 | 6 1/12" | 15 1/2 cm |
| 9 | 25 | 8 | 6 1/4" | 15 4/5 cm |
| 9.5 | 26 | 8.5 | 6 5/12" | 6 1/3 cm |
| 10 | 27 | 9 | 6 7/12" | 16 3/4 cm |
| 10.5 | 27 | 9.5 | 6 3/4" | 17 1/5 cm |
| 11 | 28 | 10 | 6 11/12" | 17 3/5 cm |
| 11.5 | 29 | 10.5 | 7 1/12" | 18 cm |
Youth Size Conversions
| U.S. SIZE | EURO SIZE | UK SIZE | INCHES | CM |
| 12.5 | 30 | 11.5 | 7 5/12" | 18 4/5 cm |
| 13 | 31 | 12 | 7 7/12" | 19. 1/4 cm |
| 13.5 | 31 | 12.5 | 7 3/4" | 19 3/5 cm |
| 1 | 32 | 13 | 7 1/3" | 18 3/5 cm |
| 1.5 | 33 | 14 | 7 1/2" | 19 cm |
| 2 | 33 | 1 | 7 2/3" | 19.5 cm |
| 2.5 | 34 | 1.5 | 7 5/6" | 20 cm |
| 3 | 34 | 2 | 8" | 20 1/3 cm |
| 3.5 | 35 | 2.5 | 8 1/6" | 21 3/4 cm |
| 4 | 36 | 3 | 8 1/3" | 21 1/5 cm |
| 4.5 | 36 | 3.5 | 8 1/2" | 21 3/5cm |
| 5 | 37 | 4 | 8 2/3" | 22 cm |
| 5.5 | 37 | 4.5 | 8 5/6" | 22 2/5 cm |
| 6 | 38 | 5 | 9" | 22 4/5 cm |
| 6.5 | 38 | 5.5 | 9 1/6" | 23 1/3 cm |
| 7 | 39 | 6 | 9 1/3" | 23 7/10 cm |
Please Note: Most manufacturers have their own specific sizing. If you have any questions, please feel free to contact our Customer Service Team.
OS1st AC4 Active Comfort Socks - No Show - Black / Small: Men's 4-6 / Women's 4-6.5 is backordered and will ship as soon as it is back in stock.
About the OS1st AC4 Active Comfort Socks - No Show
Product Details
Overview:
The OS1st AC4 Active Comfort Socks - No Show are built with two of OS1st's signature technologies, a nano-bamboo charcoal cushion and OS1st’s cooling Skin Thin™ Technology for temperature regulation for the ultimate comfort experience! These socks feature blister protection, contoured padding, and a light to moderate compression for the perfect comfort and fit.
Product Features:
- 4 Zones of Compression Technology
- Made with ultra-soft nylon treated with silver-ion technology for anti-bacterial odor and moisture wicking ability
- Cushioned with Nano Bamboo Charcoal ionized fibers for durable softness
- Skin Thin ™ Technology to increase air flow and temperature regulation
- Seamless construction
- Left/right design for anatomical fit
- Y-Gore heel
- Medical-grade light to moderate compression
- Latex-free
- Each package contains one pair
Care Instructions:
- Hand wash and hang dry. Do not use bleach products on socks.
Ideal For:
- Foot conditions: Blister protection, foot fatigue, arch pain, heel pain, hypersensitivity, overheating, sweating
4 Zones of Compression:

Sizing:
- Small: Men's 4-6 / Women's 4-6.5
- Medium: Men's 6.5-9.5 / Women's 7-10
- Large: Men's 10-12.5 / Women's 10.5+
- X-Large: Men's 13-15
Item #: OS1-AC4
Use
For more information on using your new insole, visit our Help Center to see common usage FAQs.
Care
For more information on caring for your insoles, visit our Help Center to see common product care FAQs.
Warranty
For additional information on wear-test guarantees, see our Returns Policy.
Returns
All products — except for gift cards, clearance items, and closeout items — may be returned within 60 days of delivery so long as the product is in brand-new, unworn, unused condition and is returned in the original product condition along with all of the original product packaging and labels.
Products with wear-test guarantees can be returned even if used/worn. See our Returns Policy for more information.








