A protest has been held outside Amazon’s distribution centre in Fife against low wages and working conditions.
The union says employees at the site in Dunfermline are paid £6.20 an hour, just 1p above the minimum wage. They also claim staff are made to wear digital terminals on their arms which track their movements and there are no regular breaks.
GMB say there is a culture of bullying and harassment within the company.
The protest will also be demanding Amazon pay their taxes, after the company paid just £2.3m in corporate tax despite making £7.1bn in sales.
In response, Amazon said they give staff a "safe and positive working environment" and pay all "applicable taxes".
But Paul Clarke from GMB said the "exploitation" of the staff needs to be exposed.
Mr Clarke said: "The high tech way Amazon process orders and tracks inventory disguises that it is also a traditional labour intensive mail order retail business.
"Where it differs from other retailers is its refusal to pay proper taxes or to treat its workers properly. Profitable companies like Amazon dodging fair taxes while failing to pay their staff a living wage and treat them properly deserve a corporate ASBO.
"Paying a minimum wage rather than a living wage obliges taxpayers top up wages for staff with families and is a subsidy to a company paying no corporation taxes.
"Requiring employees to wear AMTs and subjecting them to dataveillance, while denying them union rights, takes away the consent essential for the positive use of digital arm-band devices. Members say it is human automation – they are kind of robots with no say.
"GMB members at the company say that the name Amazon has become a dirty word among their friends and family and Amazon are now swimming against the tide of public sentiment."
In a statement, Amazon said: "We are proud of providing our associates with a safe and positive working environment, which includes on-the-job training and opportunities for career progression. We offer a competitive package which includes base wage and performance-related pay which increases take home pay for most employees.
"With a focus placed on ownership, permanent employees also benefit from stock grants, healthcare, a personal pension plan, life assurance, income protection and an employee discount.
"Amazon has invested over £1bn in our UK operations and employs more than 5000 permanent employees across the UK in addition to thousands of temporary associates. We continue to hire across the UK fulfilment centre network where we will create more than 2000 new permanent jobs in the next two years.
"Amazon pays all applicable taxes in every jurisdiction that it operates within."