knurling

The cup is placed on the end of the filter, which engages the knurling.

His aura was a knurling of anger and resolve.

Knurling: Produces a regular cross-hatched pattern in work surfaces intended to be gripped by hand.

A hybrid of Annular Rings and Linear Knurling in which a diamond shape is formed.

Knurling is a manufacturing process, typically conducted on a lathe, whereby a diamond-shaped (criss-cross) pattern is cut or rolled into metal.

Knurling is also used on the grips of darts and the pegs of most BMX bicycles.

Another visual difference from typical Olympic bar or IPC approved one is that the IPF bar's knurling shall not be covered by chrome.

If no knurling is present, or if the cap offers no purchase for pliers, it is probably a press-fit type and can be pried off using a thin-bladed screwdriver.