Custom Built. Commercial Quality. Complete Security.

Master Lock is recognized around the world as the authentic, enduring name in padlocks and security products. Since our founding in 1921, we have worked hard to earn and maintain the trust of our customers by delivering on our promise of strength and quality and by continually setting new standards for lock design, application and performance. As the largest global manufacturer and marketer of padlocks, we continue to build our founder’s passion for innovation, quality, and compelling value into our expanding lines of security solutions.

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4400D and 4401DLH Bluetooth® Smart Padlocks

Your Smartphone is the Key

Master Lock Bluetooth® Smart Padlocks turn your smart device into a key! With an advanced, easy-to-use app, you don’t have to worry about losing keys, forgetting combinations, or unauthorized key duplication. True keyless convenience provides greater control and flexibility as you share access with friends, family, colleagues and employees. Enjoy peace of mind as you monitor the lock’s activity and receive tamper alerts and low battery notifications. With anti-shim technology offering maximum security, these padlocks combine ergonomic features with strength, durability and reliability, making them the perfect choice for use at home, office, job site or school.

4400D Indoor Model

Best suited to indoor uses, including lockers for school, health club, workplace settings, cabinets, rental/storage units, and other indoor applications where shared access is desired in office, retail, professional services and other small business environments.

4401DLH Outdoor Model

Best suited to outdoor uses, including sheds, gates, fences, storefronts, garages, cabinets and tool storage in residential, construction, self-storage, retail, property maintenance and other small business and service environments.

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