Retirning Goods bought online

[atkinsonr]

Hope someone can give me some advice out there. I bought some horse mats a few weeks ago (they are put into the ground to stop erosion around gateways - just to give you some background in case you're wondering what on earth the are!). Unfortunately they are unsuitable, I notified the company I bought them from and asked to return them. There were no terms of condition stated on their website whatsoever, or on the delivery note, however I have just reveived an email off them saying that they will collect them but will charge me a 30% re stocking fee. Obviously a refund of 70% is better than nothing but I was just wondering if they can do this? Thanks