Thunder bolts for fixing base plated fence posts into concrete, in M10 x 75, M10 x 100, M12 x 100 and M12 x 130. Priced individually, order what this job needs.

Thunder bolts screw straight into a drilled hole in concrete, so a base plated post can be fixed down to an existing slab without resin, shields or waiting for anything to cure.

Which size for which post?

Bigger and taller posts carry more leverage at the base plate, so they want a longer, thicker anchor. As a starting point:

• 1.2m to 1.5m post — M10 x 75
• 1.8m to 2.0m post — M10 x 100
• 2.4m post — M12 x 100
• 3.0m post — M12 x 130

This is a guide only. The fixing you install is your responsibility: the slab has to be sound, deep enough and in good condition, and edge distances matter. If you are not certain the concrete will take it, get it checked before you drill.

Key points

• No resin, no shields — drill, drive, done.
• Four sizes covering the usual run of fence post heights.
• Priced individually — a base plate takes several, so count the plates and order to suit.

What else you might need

See the full nuts and bolts range, our gate accessories, and the posts and panels they fix: steel palisade, mesh fencing and railings.

Delivery and trade pricing

Fixings go out by courier, or collect from our Liverpool yard with the rest of your order. Trade accounts get bulk pricing across the range.