Doppio espresso.A single shot of espresso, by contrast, is called a solo ('single') and was developed because it was the maximum amount of ground coffee that could practically be extracted by lever espresso machines. At most cafs outside of Italy, a doppio is the standard shot.
Breville Espresso Coffee Makers. Third wave specialty coffee sees coffee as an artisanal food, produced to achieve the ultimate taste experience.
Bring a unique coffee making experience home with Nespresso's Vertuo dual coffee and espresso makers, available in a range of sizes and colors.

PIXAPRESSO electric portable espresso maker with espresso shot, coffee grounds, and capsule.It makes perfect espresso, and it costs a fraction of what other espresso machines cost. Do yourself a favour and get one. - Antony L.
Home Espresso Machine Care 101. Single VS Double Espresso Shots: What's The Difference?Traditionally, a single shot (solo) of espresso uses 7g of espresso-fine grounds and yields about 30ml of espresso (about 1 liquid ounce).

Manual Home Espresso Maker: Portable Handheld Espresso Makers.
Perfect espresso anywhere with this 670g portable coffee maker. 20 bar pressure, 3*2500mAh battery, works with grounds or capsules. Ideal for travelers and outdoor enthusiasts who demand quality coffee on the go.