Contacts for a print particle input recess

A printing device comprising a print particle input, the print particle input comprising:

• a static base structure;
• a rotating annular structure situated on the static base structure, the rotating annular structure comprising a slot to engage a counterpart structure of a print particle replenishment device;
• and
• a plurality of contacts disposed on an inner surface of the slot to mechanically contact and rotate with counterpart contact pads of the print particle replenishment device.

A method, comprising:

• receiving, via a plurality of rotating contacts, print particle replenishment device authentication data;
• unlocking a latch to allow rotation of a rotating annular structure into a docked position in response to verifying the print particle replenishment device authentication data;
• determining that the rotating annular structure is in the docked position;
• locking the latch to prevent rotation of the rotating annular structure;
• receiving an indication that a transfer of print particles is complete;
• and
• unlocking the latch to allow rotation of the rotating annular structure to an undocked position.