Hardpoint

A hardpoint is a weapons mount on a military vehicle where bombs, missiles, etc., can be attached.

In Transformers toy design, the word generally refers to a specialized type of peg that is designed to hold a Mini-Con. It may also refer to any peg, hole, or other built-in object where something connects. This "something" can be anything from accessories to other robots. For example, the entire Energon toyline has a place where weapons and Energon stars can attach in vehicle or beast mode, while Combiner robots have special hardpoints for connecting to other robots or Combiner kibble.