They're not kidding when they say their keyboards make an audible "click" sound... they also sell: Reusable Earplugs: "Multi-use, comfortable earplugs for co-w

They're not kidding when they say their keyboards make an audible "click" sound... they also sell: Reusable Earplugs: "Multi-use, comfortable earplugs for co-workers or significant others of Das Keyboard Professional or Das Keyboard Ultimate users."