Manufacturers guarantees are separate from the automatic rights you have against the seller, and may be more limited. The length of the guarantee does not limit any claim you may make against the seller. If a product develops a fault outside the guarantee period you can still claim against the seller if you can show that the fault was an unreasonable event at that time in the products life.
Your statutory rights against the seller exist whether or not you chose to buy their warranty or whether the goods came with any guarantee. So, as long as your rights under the Sale of Goods Act have been infringed you have every right to pursue the seller.
If a product is unsafe and causes any personal injury or over £275 worth of property damage, the person affected can make a claim direct against the manufacturer.
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