Jet.com has yet to launch its online retail site to the public, but has already drawn attention as a would-be game-changer that could take on Internet giant Amazon. Jet has raised $220 million so far for an e-commerce service with some 1,600 retail partners, and plans to sell some 10 million products when it launches in the coming weeks.The startup will charge $49 a year for membership to allow consumers to get "the lowest price on anything they buy online," according to a Jet spokesman. With Jet.com in its beta testing phase, a number of media reports showed that its prices on goods ranging from electronics to household products are lower than those of Amazon. Jet will use dynamic pricing which can change with the number of items placed in a basket. This is done by a team of engineers who are "constantly recalculating which seller can send that entire order to you most efficiently and cheaply," the spokesman said.Jet is led by Marc Lore, a founder of online retailer Quidsi - including diapers.com and soap.com - sold to Amazon in 2011. Some analysts say it may difficult to get a toehold in a sector led by Amazon, which sells not only physical goods but connects with customers though ebooks, music, video and other services which won't be available on Jet.com.