General description Specifically designed to attach wood to light section steel (Max. 5mm), the TIMCO Self-Drilling Wing-Tip Steel to Timber Light Section Silver Screws feature a coarse self-tapping thread with wings that ream out the timber, allowing the screw to achieve maximum R.P.M. without burning out. When the wings hit the metal, they will break off to prevent damage. Technical specifications Dimensions: 5.5 x 150 mm Material: Steel Thread type: Coarse self-tapping Maximum steel thickness: 5 mm