How Do They Do It?

E1 Aluminium Cans, Cuckoo Clocks, Paddleboards E2 Car Shredder, Sarees, Worcestershire Sauce E3 Mardi Gras, Rock Candy, Dentures E4 Helmets, Tea, District Heating E5 Royal Enfield, Art Fraud, Milk E6 Crash Testing, Delftware, Umbrellas E7 Iron Ore, Wave Flume, Chandeliers E8 Oyster Knives, Stadium Lights, Diamonds E9 Cheddar Cheese, CPR Mannequins, Dishwashers E10 Ford Transits, Driza-bone, Saltfish E11 Wood Stoves, Indigo, Synthesiser E12 Morgan Cars, Bamboo Cotton, Toilets E13 Wind Turbines, Car Tyres, Mushrooms E14 Ammo, Dental Drill, Road Markings E15 Giant Power Station, Smallest Aircraft E16 Crayons, Mirrors E17 Electric Race Cars, Mead E18 Steam-Powered Boat, Waterwall E19 Paving Stones, Tuxedo E20 Fire Gloves, Enamel