The Master Lock No. S3081 Adjustable Ball Valve Lockout features durable, lightweight Zenex™ Thermoplastic material to withstand chemicals and extreme temperatures. Device is easy to use and prevents accidental activation of a closed ball valve. The adjustable design fits 1/2in (25mm) to 2in (51mm) valves and four locking holes accept all American Lock® and Master Lock® safety padlocks.