For Australians, you will be covered Australian consumer protection laws. The manufacturer warranty does not replace your rights provided by these laws. Although a manaufacturer may provide a 12 month warranty, your actual warranty provided by ACCC may actually be longer. For example, some products you may expect to last 2 - 3 years, so under Australian consumer laws, the manufacturer would be responsible for providing a remedy for any problems with the product in that timeframe. I would expect my Band 2 to last at least that long with moderate use. Having my strap split is not acceptable at three months, let alone 18 months so I would take it back to where you bought it, and refer them to the ACCC website.
Note that if the product does not do what it is intended to do and the quality is not acceptable, then it should be repaired, replaced or a refund provided. Note that you DO NOT have to return it to the manufacturer.
Consumer guarantees on products and services (from ACCC website - Australia)
Since 1 January 2011, the following consumer guarantees on products and services apply.
Products must be of acceptable quality, that is:
•safe, lasting, with no faults
•look acceptable
•do all the things someone would normally expect them to do.
Acceptable quality takes into account what would normally be expected for the type of product and cost.
Products must also:
•match descriptions made by the salesperson, on packaging and labels, and in promotions or advertising
•match any demonstration model or sample you asked for
•be fit for the purpose the business told you it would be fit for and for any purpose that you made known to the business before purchasing
•come with full title and ownership
•not carry any hidden debts or extra charges
•come with undisturbed possession, so no one has a right to take the goods away or prevent you from using them
•meet any extra promises made about performance, condition and quality, such as life time guarantees and money back offers
•have spare parts and repair facilities available for a reasonable time after purchase unless you were told otherwise.
Who to claim a remedy from
Products
You can claim a remedy from the retailer if the products do not meet any one or more of the consumer guarantees, with the exception of availability of spare parts and repair facilities.
The remedies you can seek from the retailer who sold you the product include a repair, replacement, or refund and in some cases compensation for damages and loss.
The retailer can’t refuse to help you by sending you to the manufacturer or importer.
You can claim a remedy directly from the manufacturer or importer if the goods do not meet one or more of the following consumer guarantees:
•acceptable quality
•matching description
•any extra promises made about such things like performance, condition and quality
•repairs and spare parts - the manufacturer is responsible for ensuring that spare parts and repair facilities (a place that can fix the consumer’s goods) are available for a reasonable time after purchase unless you were told otherwise. How long is ‘reasonable’ will depend on the type of product.
You are only entitled to recover costs from a manufacturer or importer, which include an amount for reduction in the product’s value and in some cases compensation for damages or loss.