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ALL BOOTS ARE HANDCRAFTED,❗NOT MASS PRODUCED

ALL BOOTS ARE HANDCRAFTED, ❗NOT MASS PRODUCED

KING WELT • ULTRA FLEX SERIES

Double the Convenience.
Built to Move.

Lightweight flexibility, double-zipper convenience, and dependable performance in premium brown leather.

MEET THE ULTRA FLEX 339

Easy to Wear.
Ready to Perform.

The King Welt Ultra Flex 6" Brown Double-Zipper Work Boot combines job-ready durability, lightweight flexibility, and quick on-and-off convenience in a rich brown finish.

Premium full-grain leather, welt construction, an insulated textile lining, and a dual-density polyurethane sole provide the support, traction, and comfort needed for demanding all-around work.

Ultra Flex at a Glance

6" HEIGHT DOUBLE ZIPPER FULL-GRAIN LEATHER SOFT TOE LIGHTWEIGHT SLIP RESISTANT 60-DAY WARRANTY
01

Double-Zipper Entry

Dual side zippers make the Ultra Flex quick and easy to put on and remove while helping provide a secure, comfortable fit.

02

Lightweight Flexibility

The dual-density polyurethane sole delivers heavy-duty support without the unnecessary weight and stiffness of a traditional work boot.

03

All-Shift Comfort

The Anti-Fatigue Insole and insulated textile lining help keep your feet cushioned, supported, and comfortable through long shifts.

DOUBLE-ZIPPER CONVENIENCE

Get Ready Faster.
Work Without Limits.

The double-zipper design provides convenient access from either side, making the Ultra Flex easy to wear without sacrificing the dependable fit needed for active work.

Fast entry and removal

Convenient dual zippers

Flexible 6-inch profile

DUAL-DENSITY POLYURETHANE SOLE

Stable Underfoot. Flexible in Motion.

The lightweight dual-density polyurethane sole combines heavy-duty durability with technology engineered for stability, flexibility, and lasting comfort.

LIGHTWEIGHT FLEXIBLE DUAL DENSITY STABLE HEAVY-DUTY

Confident Traction

Oil- and slip-resistant traction helps support stable movement across changing work surfaces while maintaining the flexibility needed for active jobs.

PREMIUM MATERIALS

Full-Grain Brown Leather

The full-grain leather upper offers oil- and water-resistant properties, while the insulated textile lining adds comfort and warmth through changing work conditions.

Performance Underfoot

OIL RESISTANT SLIP RESISTANT STABLE FLEXIBLE COMFORTABLE

Made for the Way You Work

Construction
Warehousing
Shop Work
Outdoor Work
All-Around Work
View All Product Details
  • Style: Ultra Flex 339
  • Height: 6 inches
  • Color: Brown
  • Upper: Full-grain leather
  • Leather properties: Oil and water resistant
  • Toe type: Soft toe
  • Closure: Double side zipper
  • Lining: Insulated textile
  • Construction: Welt
  • Insole: Anti-fatigue comfort insole
  • Sole: Dual-density polyurethane
  • Outsole: Oil and slip resistant
  • Performance: Lightweight, flexible and heavy-duty
  • Use: All-around work
  • Warranty: 60 days
How Does the Ultra Flex Fit?

King Welt boots are designed to fit true to size. Order your regular boot size for the best fit. If you wear thick work socks or prefer additional room, consider going up half a size.

How Do I Care for Them?

Brush away loose dirt after wear and clean the leather with a slightly damp cloth. Allow the boots to air-dry naturally away from direct heat. Apply a suitable leather conditioner when needed, testing it on a small hidden area first because conditioning may darken the brown leather.

60-Day Warranty

The Ultra Flex 339 includes a 60-day warranty. Please review King Welt’s current warranty terms and conditions for complete coverage details.

KING WELT ULTRA FLEX

Zip In.
Get the Job Done.

Step into double-zipper convenience, lightweight flexibility, dependable traction, and rich brown leather.

DOUBLE THE CONVENIENCE • READY FOR WORK

All boots are true to size*

4% off

Ultra Flex 6" Brown Double Zipper Work Boots Soft Toe, Full-Grain Leather.

SKU: KW339BRN-6
Regular price $134.99 $129.00 4% off
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KING WELT • ULTRA FLEX SERIES

Double the Convenience.
Built to Move.

Lightweight flexibility, double-zipper convenience, and dependable performance in premium brown leather.

MEET THE ULTRA FLEX 339

Easy to Wear.
Ready to Perform.

The King Welt Ultra Flex 6" Brown Double-Zipper Work Boot combines job-ready durability, lightweight flexibility, and quick on-and-off convenience in a rich brown finish.

Premium full-grain leather, welt construction, an insulated textile lining, and a dual-density polyurethane sole provide the support, traction, and comfort needed for demanding all-around work.

Ultra Flex at a Glance

6" HEIGHT DOUBLE ZIPPER FULL-GRAIN LEATHER SOFT TOE LIGHTWEIGHT SLIP RESISTANT 60-DAY WARRANTY
01

Double-Zipper Entry

Dual side zippers make the Ultra Flex quick and easy to put on and remove while helping provide a secure, comfortable fit.

02

Lightweight Flexibility

The dual-density polyurethane sole delivers heavy-duty support without the unnecessary weight and stiffness of a traditional work boot.

03

All-Shift Comfort

The Anti-Fatigue Insole and insulated textile lining help keep your feet cushioned, supported, and comfortable through long shifts.

DOUBLE-ZIPPER CONVENIENCE

Get Ready Faster.
Work Without Limits.

The double-zipper design provides convenient access from either side, making the Ultra Flex easy to wear without sacrificing the dependable fit needed for active work.

Fast entry and removal

Convenient dual zippers

Flexible 6-inch profile

DUAL-DENSITY POLYURETHANE SOLE

Stable Underfoot. Flexible in Motion.

The lightweight dual-density polyurethane sole combines heavy-duty durability with technology engineered for stability, flexibility, and lasting comfort.

LIGHTWEIGHT FLEXIBLE DUAL DENSITY STABLE HEAVY-DUTY

Confident Traction

Oil- and slip-resistant traction helps support stable movement across changing work surfaces while maintaining the flexibility needed for active jobs.

PREMIUM MATERIALS

Full-Grain Brown Leather

The full-grain leather upper offers oil- and water-resistant properties, while the insulated textile lining adds comfort and warmth through changing work conditions.

Performance Underfoot

OIL RESISTANT SLIP RESISTANT STABLE FLEXIBLE COMFORTABLE

Made for the Way You Work

Construction
Warehousing
Shop Work
Outdoor Work
All-Around Work
View All Product Details
  • Style: Ultra Flex 339
  • Height: 6 inches
  • Color: Brown
  • Upper: Full-grain leather
  • Leather properties: Oil and water resistant
  • Toe type: Soft toe
  • Closure: Double side zipper
  • Lining: Insulated textile
  • Construction: Welt
  • Insole: Anti-fatigue comfort insole
  • Sole: Dual-density polyurethane
  • Outsole: Oil and slip resistant
  • Performance: Lightweight, flexible and heavy-duty
  • Use: All-around work
  • Warranty: 60 days
How Does the Ultra Flex Fit?

King Welt boots are designed to fit true to size. Order your regular boot size for the best fit. If you wear thick work socks or prefer additional room, consider going up half a size.

How Do I Care for Them?

Brush away loose dirt after wear and clean the leather with a slightly damp cloth. Allow the boots to air-dry naturally away from direct heat. Apply a suitable leather conditioner when needed, testing it on a small hidden area first because conditioning may darken the brown leather.

60-Day Warranty

The Ultra Flex 339 includes a 60-day warranty. Please review King Welt’s current warranty terms and conditions for complete coverage details.

KING WELT ULTRA FLEX

Zip In.
Get the Job Done.

Step into double-zipper convenience, lightweight flexibility, dependable traction, and rich brown leather.

DOUBLE THE CONVENIENCE • READY FOR WORK

All boots are true to size*

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