M12x220 Cup Square Hex Coach Bolts Galvanised Bolt Only

• These coach bolts are galvanised, and ideal for timber to timber joining.
• Coach bolts upto 100mm are fully threaded, over 100mm will have a minimum of 100mm of thread unless stated.
• M8, M10 and M12 galvanised versions do not come supplied with any nuts.
• Also known as 'cup square hex bolts', the square underneath the cup stops rotation of the bolt when tightening.
• Conforms to DIN603 and DIN934 standards.
• Available in a comprehensive range of sizes to suit most applications.

APPLICATION
Used mainly for fastening timber to timber and is extensively used for timber joist construction in house building and numerous decking applications.

A carriage bolt, also known as coach bolt or as cup square hex bolts, has a domed head, and the shank is topped by a short square section under the head. The square section grips into the part being fixed (typically wood), preventing the bolt from turning when the nut is tightened. A rib neck carriage bolt has several longitudinal ribs instead of the square section, to grip into a metal part being fixed.

Galvanised coatings prevent oxidation of the protected metal to create a longer lasting finish. It does this by forming a barrier and by acting as a sacrificial anode if this barrier is damaged. Galvanise is a coating that (in contrast to iron oxide) does not trigger a breakdown of the substrates surface integrity as it is formed. The galvanise, if left intact, can act as a barrier to further oxidation, in a way similar to the protection afforded to aluminum and stainless steels by their oxide layers.

Fastener Specifications
Head Type	Cup Square Hex
Bolt Diameter	12mm
Fixing Length	220mm
Thread Length	100mm
Thread Type	Metric
Thread Pitch	1.75mm
Bolt Finish	Galvanised
Material Grade	4.6 Mild Steel
Bolt Specification	DIN 603/1230