A connector system including a first connector body, a second connector body configured to mate with the first connector body, a locking feature configured to secure the second connector body to the first connector body, and a connector position assurance (CPA) device that, when engaged, inhibits operation of the locking feature. A portion of the second connector body and the CPA device cooperate to form a box to completely enclose the locking feature, thereby inhibiting disengagement of the CPA device from the locking feature. The CPA device has a flexible lock arm configured to secure the CPA device to the second connector body. A portion of the CPA lock arm may be configured to be frangible. The second connector body and/or the CPA device may define an aperture configured to provide access to the CPA lock arm. The aperture is at least partially blocked by a frangible tab.