Trying to access the Slider component

im trying to access the Slider component but there's no Slider component apparently:

 using UnityEngine;
 using System.Collections;
 
 public class QSlider : MonoBehaviour {
     private float slider;
     void Start()
     {
         slider = GetComponent<Slider>();
     }
 }

and the error is:

And finally the inspector...

Thanks!