This is a finger knuckle, it has two types, one is pointy and the other is pointier, it's sole purpose is to be used in emergency cases, like in a dark alley or in a fist fight (life or death situation or assault situation)

I've printed this model in several types of polymers, but the ones that usually lasted more were those printed using PETG, not ABS, not PLA (if you desire printing it in nylon it will last even more)

The printing settings are: 

• at least 3 perimeters/walls 
• 20% ~ 30% infill density (gyroid)
• at least 4 bottom and top layers
• If you want the knuckles to last for a fair amount of time, I'd suggest to just print them solid

(I designed this based on an existing design, but the original model is no longer available)