Member States shall provide that seed potatoes may not be placed on the market unless they have a minimum size such that they do not pass through a square mesh of 25 × 25 mm. In the case of tubers which are too large to pass through a square mesh of 35 × 35 mm, the upper and lower size limits shall be expressed in multiples of five.

The maximum variation in size between tubers in a lot shall be such that the difference between the dimensions of the two square meshes used does not exceed 25 mm. These sizing standards may be modified in accordance with the procedure referred to in Article 25(2).

A lot shall not contain more than 3 % by weight of tubers smaller than the minimum size indicated or more than 3 % by weight of tubers larger than the maximum size indicated.

Member States may, in respect of seed potatoes produced in their national territory, further reduce the permitted variation in size between tubers in a lot.