Mars Bar from the 1990s found during house clearance

Mars Bars are made by US company Mars, Incorporated.

The manufacturer also owns several other chocolate brands including Celebrations chocolate tubs, Galaxy, Hotel Chocolat, M&Ms and Maltesers.

It also owns non-chocolate brands including Dreamies, Hubba Bubba, Pedigree and Whiskas.

The company was founded in 1883 by Frank C Mars, from Minnesota, with his mother Elva teaching him how to hand-dip chocolate.

Mars Bars were first made by hand in Slough, Berkshire in 1932 and are still made in the town.

A Mars spokesperson said: "Over the last 35 years, we have made a number of updates to our bar sizes and pack formats to reflect consumer demand, alongside considering wider external factors such as manufacturing costs and the price of cocoa."

Reporting from BBC News contributed to this story.