Gizmos.DrawWireCube

Description

Draw a wireframe box with center and size.

    function OnDrawGizmosSelected () {
        // Draw a yellow cube at the transforms position
        Gizmos.color = Color.yellow;
        Gizmos.DrawWireCube (transform.position, Vector3 (1,1,1));
    }

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void OnDrawGizmosSelected() {
        Gizmos.color = Color.yellow;
        Gizmos.DrawWireCube(transform.position, new Vector3(1, 1, 1));
    }
}