Martin Yale 62001 Deluxe High-Speed Letter Opener, Gray, Up To 17,500 Envelopes per Hour, Accepts a 6" Tall Stack of Envelopes, 500,000 per Month Capacity For high-speed processing of large mail volume Automatically feeds, opens and collects a stack of envelopes Operates at a speed of up to 17, 500 envelopes per hour Opens envelopes up to 1/4 Inches thick and stacks up to 6 Inches Comes with removable receiving tray