This is a simple plug to occupy the void on the backside of the filament cutter top lever block on the Bambu Lab A1. (note: this is ONLY for the A1, and will not fit the mini, as the two have different dimensions.) Another Maker here on Makerworld already has an excellent one for the A1 Mini - go check them out: https://makerworld.com/en/models/240398?from=search#profileId-256286