Dell TT4RM is an AC adapter for Dell laptops that require this adapter specification. Its rated output is 180 W at 19.5 V, providing external power during ordinary computer use.
The laptop-side connector has three pins and a diameter of 7.4 mm, so these details can help identify the matching physical connection. The listing also specifies a C6 power cord.
Together, the output rating and connector format describe which systems this version is intended for. Check that the laptop uses the same adapter specification and connector before choosing it.