Manx drinks measures look set to shrink by more than eight per cent, according to pub landlords.
Four publicans have told 3FM the Office of Fair Trading wants to recommend spirits measures be changed to those found in the UK.
Earlier this year the OFT consulted on proposals to make Manx pub measures around 24 millilitres - currently they're around 28.
The move would mean pubs could buy standardised optics and glasses instead of having to have them specially made.
A spokesman for the OFT says no decision has yet been made.
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