NuSet Smart-Box series 2nd generation electronic combination lock box with resettable 4-number combo locking shackle. Features Designed and assembled in the USA Large and durable metal casing for keys and credit card storage Control access via day and time or duration-limited access codes* Allow access via one-time remote access codes Program lock box with the ease of USB device Retrieve access log with date and time Weather resistant provided the lockbox is in closed position and is hanged vertically No subscription required No internet access required No access card to buy * Program up to 500 4 to 6-digit codes System Requirements 32-Bit or 64-bit Windows®-based computer with Java installed Mac OS X with Java installed Windows® XP, Windows Vista®, Windows® 7, Windows® 8 or Windows® 10 USB port Parts Included Electronic Lockbox USB flash drive with application and user guide preloaded External battery cable adapter Reset Tool 4 Lithium AA Battery Optional Accessories Key Reel Maximum Exterior DimensionHeight (w/o Shackle): 5-9/32"Width: 3-11/32"Depth: 2-17/32"Minimum Inner Vault Size3-3/8" (H) x 2-15/16" (W) x 3/4" (D)Shackle DimensionDiameter: 3/8"Vertical Clearance: 2"Horizontal Clearance: 1-1/2"