What is the relationship between Plug Power and fuel cell in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Following the Feb 2014 announcement that Plug Power will supply 1,738 GenDrive fuel cell units to Wal-Mart’s six North America distribution centers over the next two years, its shares catapulted 133.8% till almost mid March.

Answer: product_or_material_produced