First you need to be careful on the price if you buy a MAC Pigment / Eye Shadow / Lippies / Brushes or any other products cheaper than MAC, Like a MAC Pigment is 20GBP you pay 5GBP for the same size of a product.
There are new fakes that , they are nearly identical , with texture and colour , you need to consider that even on authentic MAC could have some scratches and damages, it might happen during the transport.
And there might be differences on MAC Products because MAC produces some products only for some certain countries , Like MAC does in Asia
And if the seller has that item in her/ his hand for a while, there might be damages in the box and bottle
Now Most of MAC’s limited edition items are MADE IN CHiNA
If you want to buy MAC from ebay buy it from a reputable seller
One other clue is if you scratch the box with your finger nail if it is original it won’t leave any scratch marks
Most of fake MAC products are sold from Hong Hong
MAC always names their eyeshadows. Fake eyeshadows will often only label the stickers with number/letter codes.
MAC eyeshadows should have a flip top not a twist of cap
Some Sellers remove the label on the bottom of the products if i am not wrong that label is called UPC , they do this because they do not want their customer to take the product to MAC Counters
Authentic MAC eyeshadow do not come with a sponge applicator and mirror, Single eye shadows some eye shadow palettes comes up with a mirror and not a sponge applicator but a small size brush this an authentic MAC Eye shadow Palette
I am not sure how true is this information but, as i read in forums, paypal is not covering for buyers if they purchased a fake mac product, they are asking a proof document, And as I know MAC Cosmetic counter refused to give a proof of letter or a document because it has been purchased online not from MAC Cosmetics
Beaware that MAC has changed the packing of their pigments,
On the bottom of the box there should be a bar code label printed on a sticker. If the bar code is printed directly onto the bottom of the box then the product is a fake.
Actually I do not know where i got this brush, but it was really cheap, and i do not want to use my MAC 239
As you can see from the pictures it is similar to MAC
unfortunately it is not as soft as MAC 239, it was soft at first, but now it is really hard to do eye make up with it now, i feel i like am using a brush made of cactus
it looks the same top the bottom but MAC has softer hair and this does not