Timco Box of 100 x WingTip Screw S/DRILL No4 Zinc – 5.5 x 85 – HW85B

Specifically designed to attach wood to heavy section steel (Max. 12mm). Metric thread with wings designed to ream out the timber> so the screw can achieve Max. R.P.M. without burning out. When the wings hit the metal they will break off to permit the thread to self-tap into the metal. 100 Pieces