We would advise weighing your items to the best of your ability, in order to avoid any overweight charges.
For our domestic routes (NI-UK and UK-UK) The maximum weight per item is 30kg.
For the rest of the routes, you can send more than 30kg per item - but there may be an oversize charge for this.
To weigh your items, we recommend weighing your box/suitcase using some sort of weighing equipment. We recommend bathroom or normal scales or also hand-held luggage scales. They can usually be purchased on Amazon for a small fee.
If you are unsure of the exact weight, please overestimate it slightly - to allow room for error.
If your bathroom scales perhaps may be older and will not weigh a suitcase, you can weigh yourself holding the item you are going to send. If you then weigh yourself as normal (without the item) the difference will be the weight of your item. You may need assistance from someone for this.