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ALL BOOTS ARE HANDCRAFTED,❗NOT MASS PRODUCED

ALL BOOTS ARE HANDCRAFTED, ❗NOT MASS PRODUCED

Ultra Flex • Style 336

Fast On. Work Ready.
Built for Comfort.

A lightweight 6-inch work boot with dual side zippers, rugged full-grain leather and dependable comfort for demanding workdays.

Dual Side Zippers Soft Toe Full-Grain Leather Oil & Water Resistant Insulated Lining 30-Day Warranty

Easy Entry. Serious Performance.

The Ultra Flex 6" Black Double Zipper Work Boot is made for workers who want dependable performance without unnecessary weight. Its two side zippers make getting ready fast, while the full-grain leather upper, welt construction and dual-density polyurethane sole provide the durability, flexibility and stability needed for long days on the job.

01

Zip In & Go

Dual side zippers provide quick entry and removal while maintaining the secure feel of a supportive work boot.

02

Lightweight Strength

The dual-density polyurethane sole balances lightweight mobility with the durability required for demanding work.

03

All-Day Comfort

An antifatigue insole and insulated textile lining help support comfortable wear throughout long shifts.

Ultra Flex Convenience

Double-Zipper Access

Zippers on both sides open the boot wider for faster entry and removal—an ideal feature for workers who need to get moving without wasting time.

Soft-Toe Freedom

Room to Move Naturally

The soft-toe design reduces unnecessary bulk and supports natural movement for jobs that do not require a protective safety toe.

Dual-Density Technology

Lightweight Below. Heavy-Duty at Work.

The dual-density polyurethane sole is engineered to deliver stability, flexibility and cushioning without weighing you down. Oil- and slip-resistant performance helps provide more confident footing across everyday work environments.

Work-Ready Details

6-INCH
Supportive height
FULL-GRAIN
Leather upper
WELT
Construction
INSULATED
Textile lining
ANTIFATIGUE
Comfort insole
OIL & SLIP
Resistant outsole

Made for the Everyday Grind

Construction Warehousing Manufacturing Maintenance General Work
Product Details
Style: Ultra Flex 336
Color: Black
Height: 6 inches
Toe: Soft toe
Upper: Full-grain leather
Resistance: Oil and water resistant
Entry: Dual side zippers
Construction: Welt
Lining: Insulated textile
Insole: Antifatigue
Sole: Dual-density polyurethane
Warranty: 30 days
Fit & Sizing
King Welt work boots generally fit true to size. If you wear thick work socks, use an additional insert or prefer extra room, consider ordering a half size up.
Leather Care

Remove loose dirt with a soft brush or dry cloth. Clean using a product made for full-grain leather, then allow the boots to air-dry naturally away from direct heat.

Apply a compatible leather conditioner when needed and test all care products on a small hidden area before treating the entire boot.

30-Day Warranty
This product includes a 30-day warranty. Please review the current King Welt warranty terms for coverage, eligibility and claim requirements.
Ultra Flex • Style 336

Zip Up and Get to Work

Quick dual-zipper access, rugged black leather and lightweight comfort—built for workers who stay moving.

King Welt • Built for the Work

All boots are true to size*

4% off

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

SKU: KW336BLK-6
Regular price $134.99 $129.00 4% off
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Ultra Flex • Style 336

Fast On. Work Ready.
Built for Comfort.

A lightweight 6-inch work boot with dual side zippers, rugged full-grain leather and dependable comfort for demanding workdays.

Dual Side Zippers Soft Toe Full-Grain Leather Oil & Water Resistant Insulated Lining 30-Day Warranty

Easy Entry. Serious Performance.

The Ultra Flex 6" Black Double Zipper Work Boot is made for workers who want dependable performance without unnecessary weight. Its two side zippers make getting ready fast, while the full-grain leather upper, welt construction and dual-density polyurethane sole provide the durability, flexibility and stability needed for long days on the job.

01

Zip In & Go

Dual side zippers provide quick entry and removal while maintaining the secure feel of a supportive work boot.

02

Lightweight Strength

The dual-density polyurethane sole balances lightweight mobility with the durability required for demanding work.

03

All-Day Comfort

An antifatigue insole and insulated textile lining help support comfortable wear throughout long shifts.

Ultra Flex Convenience

Double-Zipper Access

Zippers on both sides open the boot wider for faster entry and removal—an ideal feature for workers who need to get moving without wasting time.

Soft-Toe Freedom

Room to Move Naturally

The soft-toe design reduces unnecessary bulk and supports natural movement for jobs that do not require a protective safety toe.

Dual-Density Technology

Lightweight Below. Heavy-Duty at Work.

The dual-density polyurethane sole is engineered to deliver stability, flexibility and cushioning without weighing you down. Oil- and slip-resistant performance helps provide more confident footing across everyday work environments.

Work-Ready Details

6-INCH
Supportive height
FULL-GRAIN
Leather upper
WELT
Construction
INSULATED
Textile lining
ANTIFATIGUE
Comfort insole
OIL & SLIP
Resistant outsole

Made for the Everyday Grind

Construction Warehousing Manufacturing Maintenance General Work
Product Details
Style: Ultra Flex 336
Color: Black
Height: 6 inches
Toe: Soft toe
Upper: Full-grain leather
Resistance: Oil and water resistant
Entry: Dual side zippers
Construction: Welt
Lining: Insulated textile
Insole: Antifatigue
Sole: Dual-density polyurethane
Warranty: 30 days
Fit & Sizing
King Welt work boots generally fit true to size. If you wear thick work socks, use an additional insert or prefer extra room, consider ordering a half size up.
Leather Care

Remove loose dirt with a soft brush or dry cloth. Clean using a product made for full-grain leather, then allow the boots to air-dry naturally away from direct heat.

Apply a compatible leather conditioner when needed and test all care products on a small hidden area before treating the entire boot.

30-Day Warranty
This product includes a 30-day warranty. Please review the current King Welt warranty terms for coverage, eligibility and claim requirements.
Ultra Flex • Style 336

Zip Up and Get to Work

Quick dual-zipper access, rugged black leather and lightweight comfort—built for workers who stay moving.

King Welt • Built for the Work

All boots are true to size*

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