Master Lock's S3920 Butterfly Valve Lockout device
Unlike other butterfly valve lockouts, the new Master Lock S3920 Butterfly Valve Lockout device slides smoothly between the valve handle and lever in open, de-energized position. Infinitely adjustable cable inserted through an eyelet keeps the device in place and the butterfly valve fully locked out.

Master Lock®Company LLC’s latest entry into the Safety Lockout/Tagout (LOTO) arena, the new S3920 Butterfly Valve Lockout, turns the tables on devices that merely clamp down on the valve handle to keep it disengaged.

The Master Lock wedge-shaped device slides smoothly between the butterfly valve handle and the lever in an open, de-energized position, and easily adjusts to fit virtually any size butterfly valve.  Feeding cable through an eyelet and around the valve neck keeps the S3920 tight and the valve fully locked out.  Applying a padlock completes the task, and it takes only 30 seconds, start-to-finish; see demonstration video at

“It’s ‘Safety Made Simple’,” observes Matt Dudgeon, Master Lock Global Safety Product Manager, commenting on the all-new, first-of-its-kind design.  “The S3920 is highly intuitive, and it can be easily and quickly applied.  Simplicity and ease of use are hallmarks of Master Lock safety products.  This Butterfly Valve Lockout advances that tradition even further, helping to ensure worker safety.”

Ideal solution in virtually any environment, with exclusive cable lockout features

Users can employ the tough, thermoplastic S3920 just about anywhere.  It is highly resistant to weather and corrosive elements, as well as chemicals found in many facility environments.  The stainless steel rivet likewise withstands such attacks, enabling the device to smoothly pivot open-and-closed to ensure a snug fit in large or small butterfly valves.

The S3920’s companion S806CBL3 Cable Lockout also repels chemicals and extreme conditions (temperatures from -40° to 200° F), and is infinitely adjustable.  A patented locking feature enables users to remove cable slack, to keep the lockout secure.

For more information on the Master Lock wedge-shaped Butterfly Valve and other Safety Lockout Products, visit  For further story details, contact Bob Wolff, The Drucker Group ( at 224-532-1808.

About Master Lock Company

Master Lock Company is the largest global manufacturer and marketer of padlocks, door hardware and related security products, including a leading assortment of safety padlocks and devices.  Master Lock Company offers a breadth of quality, innovative security solutions through expanding product lines for commercial, industrial, government, school and institutional, home and yard, automotive and recreational security markets.  Master Lock Company LLC is part of Fortune Brands Home & Security, Inc. (NYSE: FBHS), a leading consumer brands company.