Anchor design is always evolving and Ultra Marine claims its new design is the best yet. Theo Stocker tested the 12kg model, with the Ultra Flip Swivel, on his Sadler 29.

At first glance the 12kg anchor with the Ultra Flip Swivel is similar to a Spade anchor, but with curves on three planes.

The upper surface curves strongly downwards towards the tip, so that it catches and digs in even on hard, flat surfaces.

The fluke is concave side to side to prevent ploughing, and the undersides of the fluke arc downwards with side plates at the back to force the tip down.

An Ultra anchor

A hollow shank and a lead weighted tip keep the anchor the right way up. The rear bar prevents chain wrapping round the shank

The tip is filled with lead to maximise tip loading, while a hollow shank creates a stronger shape than plate metal and lowers the centre of gravity.

This weight distribution, supplemented by a central rear bar to stop the chain fouling on the shank, negates the need for a roll bar, which its makers claim can stop anchors digging in more deeply.

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The underside of the fluke rises up to a flat section at the rear, which allows the anchor to pivot upwards when being broken out.

It is made in 316L stainless steel only, as the air in the hollow sections would not withstand the hot galvanizing process.

How we tested the 12kg Ultra Anchor and Flip Swivel

We used the anchor in a range of anchorages and heavy weather was simulated with generous amounts of power astern.

We spent nights at anchor and over tide changes, and I also dived on the anchor to see how well it had set.

I was impressed with how quickly the anchor set.

An Ultra anchor being tested underwater

The Ultra Anchor was tested in a range of anchorages

While our normal 10kg Bruce anchor can struggle in soft sand and weed, the Ultra anchor buried itself almost completely and refused to drag.

On bare rock, the anchor slid across a flat piece of rock until the tip met a crevice and brought the boat up sharply.

As the tide changed, the anchor stayed lodged where it was and held the boat, even under astern power.

So the Ultra Anchor’s performance amply delivers on its maker’s promises as is comparaable to other stainless anchors.

If you’re looking at cheaper galvanized anchors, it’s quite a step up cost wise.

Flip Swivel

The Flip Swivel is a great piece of kit too.

No larger than a conventional swivel, but much smaller than other flip swivels, its ball joint reduces lateral forces by allowing 30º of movement in all directions, as well as 360º rotation.

Ultra Flip Swivel

The flip swivel has a nub at the top of the ball joint, which forces the anchor to roll the right way up

A small nub rolls the anchor the right way up as soon as the swivel hits the bow roller.

It’s made of CNC-milled stainless steel, with a breaking strain of a tonne more than our 8mm galvanized chain.


Price: From £595
Price as tested: £1,104
Sizes: 5, 8, 12, 16 up to 360kg

Flip Swivel

Price from: £222
Price as tested: £267
Sizes: 6mm-26mm


Also on the market


A Rocna anchor

Prices start from £280

The Rocna anchor is instantly recognisable with its concave fluke, sharp tip and large roll-bar.

It doesn’t have a weighted tip, putting the weight into making the anchor as strong as possible.

The high-tensile shank is designed to make the anchor self launching, and it has been shown to have high resistance to dragging.


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Buy it now on

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A Vulcan anchor

Prices start from £405

The Vulcan comes from the makers of the Rocna, but has been modified to do away with  the roll-bar, which can be cumbersome to stow on bow- rollers under bowsprit or pulpits.

It has a weighted tip, a larger, concave fluke and flared trailing edge to help roll the anchor the right way up.

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A Spade anchor

Prices start from £384

One of the first anchors to pioneer a concave fluke and weighted chamber to increase tip loading, it digs in quickly and has a high drag resistance.

The Spade is available in stainless steel, galvanized steel and aluminium, and the shank can be separated for stowage.


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Buy it now from Jimmy Green Marine