The delivery of [Products] arrived on [date]. We were disappointed with the quality of [Products] in the order. [They are not up to the usual standard of [previous orders] / [competitors] / [the sample provided].] / [[Products] do not conform to the quality [promised by you] / [expected for this product].]
[DESCRIBE THE SPECIFIC QUALITY ISSUE: e.g. easily breaks, does not work properly, flimsy, different colour, different size, does not fit, poor workmanship etc.]
[The number of complaints that I am receiving from my [customers / employees] are driving me to distraction.] [Many of our customers have asked for refunds.] / [We were left with no choice but to replace them with higher quality [Products] from another supplier].