I didn't even realise this was a thing!
I'm wearing a black sleeveless dress to a wedding, but my arms leave something to be desired! I did a bit of self-conscious googling about this and found out about 'control sleeves' - essentially lacy slightly stretchy sleeves that sit under your dress and pull your arms in a big.
M&S do some - but the cuffs on them are a bit short and loose. Are there others? Has anyone bought/used them?