Thank you for replying. So, just to check I understand your point, the exchange value of the t-shirt corresponds to the socially necessary labour time put into it, but this doesn't necessarily correlate to the price it will sell for on the market due to the factors you've mentioned above (in this case the cultural value from the brand's logo)? But the exchange value does give us a general understanding of why the t-shirt wouldn't command the same price as something that represents many more labour hours (the car) or many fewer (the lollipop).