Parcels - Small
A Small Parcel can be up to 160mm deep x 350mm wide x 450mm long.
A Small Parcel can weigh up to 2kg (2000gm) (just over 4lb).
These dimensions allow a useful quantity of material to be shipped.
First Class Small Parcels at 2kg are appreciably more expensive to send via Royal Mail. There is no 1kg step in the pricing for Second Class, there is for First Class.