This is the Black Square 4-pin plug used on most LS applications

These oxygen sensor extensions will make for an easy installation and will avoid the problems of faulty O2 sensor readings that are common with cutting and splicing.

This package contains a pair of oxygen sensors.

This package includes two 24" oxygen sensor extension cable for LS1 engines

LS1 02 Oxygen Sensor Header Extension Harness 24 inch 4-pin, O2 Extender Fitment for LS Camaro Firebird Pontiac Chevy Applications