TimberLOK is a brand of heavy duty wood screw that performs great in external applications.
TimberLOK screws are a popular brand, developed by FastenMaster, for extremely tough jobs that need a lot of hold. TimberLOK is even an excepted way of securing rafters or trusses.
The robust screw design and sharp points of the TimberLOK means it makes light work out of the toughest of timber. A free drill bit is included in the packs. Their motto clearly is to make the life of the end user as easy as possible and they achieve it.