For applications where the material thickness varies and the aesthetic is a concern, the Stanley Avdel Black Avex is the perfect solution.  It’s designed with an wide variable grip range which makes it versatile and ensures you get the correct strenght regardless of your material thickness. The aluminium body with a positively retained steel stem gives excellent hole fill. The placed fastener is resistant to the ingress of non pressurised water and air. You have the option of a wide flange or a regular flange.