Connector 1-to-1: An exact model of the connector manufactured by Rainbird. Not really printable.
Connector Printable: 1/2 of the connector, modified slightly to enhance printability (overhangs tapered). To use these, you'd have to print 2 and glue them together. For most people, this is the one you should print.
Connector Vase: This is a solid model, intended to be printed in vase-mode, using a very large nozzle (ie: 1mm). If doing so, use a ~1mm-tall, ~3mm-wide skirt, 0 bottom layers, and 0 top layers. This is only half the connector, so print 2 and glue them together afterward.