A connector for an implantable medical device includes an elongated connector housing having a first end, a second end, a length, and an outer surface. The connector housing defines a port at the second end of the connector housing that extends along the length toward the first end. The port is configured and arranged for receiving a proximal end of lead or lead extension. Connector contacts disposed in the connector housing are configured and arranged for coupling to terminals disposed on the lead or lead extension when the lead or lead extension is received by the port. At least one window is defined along the outer surface of the connector housing. The at least one window is configured and arranged for viewing at least a portion of the lead or lead extension when the lead or lead extension is received by the port.
