Lenovo offers several 19.5-inch monitors, typically designed for daily office tasks and space-saving setups.
The query could refer to a few different popular models:
ThinkVision E20-30 (A 1600 x 900 resolution business monitor with HDMI and VGA ports)
ThinkVision E2054 (A 1440 x 900 resolution IPS monitor)
Lenovo D20-30 (A budget-friendly 1600 x 900 display for home and office)

Lenovo produces several different models of 19.5-inch monitors, the exact contents of the box vary slightly depending on the specific model you have purchased (such as the Lenovo D20-30, ThinkVision E20-30, or the older LI2054).
However, you will almost always find the following core items inside a factory-sealed box for a Lenovo 19.5-inch monitor:
Standard Box Contents
Monitor Panel (Head): The actual 19.5-inch display screen.
Stand & Base: The detachable desk stand and base plate (requires quick assembly).
Power Cable: A standard 1.8-metre power cord to connect the monitor to the wall.
Video Signal Cable: Depending on your model's exact generation, you will get one of the following:
An HDMI Cable (Most common for newer models like the D20 or E20 series).
A VGA Cable (Common for older legacy models like the LI2054 or V20 series).
Model-Specific Differences
Lenovo D20-20 / D20-30 / ThinkVision E20-30:
Monitor with Stand
1 x Power cable (1.8 m)
1 x HDMI cable (1.8 m)
Quick setup guide & Warranty booklet
Lenovo LI2054 / LI2054A / V20-10:
Monitor with Stand
1 x Power cable
1 x VGA cable