What lens adapter do I need?

I'm hoping to buy this Raynox DCR-250 Macro Attachment
Http://www.amazon.co.uk/...000A1SZ2Y/" class='ext_link'>http://www.amazon.co.uk/...000A1SZ2Y/
but i'm wondering if it will fit on my Nikon D3100 with its AF-S Nikkor 18-55mm VR Lens which has a filter size of 52mm and i also have a Tamron AF 70-300mm lens which has a filter size of 62mm.
people say i need an adapter for this attachment to work.
if i do need an adapter could you please suggest which one or 2? (for both lenses) i need.

Http://www.amazon.co.uk/Raynox-RADCR-0250-DCR-250-Macro-Attachment/dp/tech-data/B000A1SZ2Y/

Let's look at some of the specifications for this item. Two things quickly stand out:

1) The lens-sided thread is only 43mm.

2) The front thread for filters is only 49mm.

What the above means is that the actual item has a smaller diameter than the front element of both of the lenses you own - 18-55mm which uses 52mm diameter filters and 70-300mm which uses 62mm diameter filters.

If you were to find a step-down adapter ring (52mm to 43mm) to allow use of a 43mm diameter item on a lens requiring a 52mm diameter filter its highly possible that even at 55mm (the long end of your 18-55mm zoom) you will experience vignetting - dark corners on your pictures. At 18mm vignetting will be even more severe. If you were to find a step-down adapter ring of 62mm to 43mm your pictures taken with your 70-300mm lens would probably be round - very severe vignetting.

In my opinion you'd be smart to forget about buying the item you show and save your money until you can afford a proper macro lens like the Nikon Nikkor 60mm micro prime lens.

Gadgets like the Raynox DCR-250 Macro Attachment seldom perform as advertised and are mostly a waste of money. Don't waste yours - save for a real macro lens.

Hmm… A macro version of a Holga.

Whenever I want to know something about a product I look at the manufacturer's website. Silly habit but I can't seem to break it.

The lens includes a snap-on universal mount suitable for 52mm to 67mm filter size.

So, no adapters needed.

@Edwin: You sir have absolutely no clue what you're talking about.

@AWBoater: No, more like a budget version of a canon 500d. These raynox things are quite capable of sharp images.

That thing is whacky. But nonetheless there's no way in hell it will fit. It is for a 43 or 49mm filter thread. You have a 52. 'aint gonna happen. Look into closeup filters.

http://www.amazon.co.uk/...n.co.uk/s/

Same idea but makes much more sense.