This is a specific replacement fuse for electrical and electronic equipment.

It's a SIBA brand ceramic tube fuse, model number 7006565.
The ratings are 500 milliamps (500mA), with a 'T' time-lag/slow-blow characteristic (so it can handle brief surges), and a high breaking capacity of 500 volts (H500V).

The physical size is a standard 6.3mm in diameter by 32mm long.

These fuses are commonly used in power supplies, industrial controls, audio equipment, and other applications where reliable circuit protection is needed.

Always make sure this matches the exact specifications (amperage, voltage, physical size, and time rating) of the fuse you are replacing.
Using the wrong fuse can be a fire hazard.
Keep a couple of these on hand if your equipment uses them – it's a small part that can save a big headache.