It is perhaps one of the most nostalgic photos for most ministers of finance whenever they walk out of Treasury building on the Budget Day.
A Treasury Secretary will not be complete walking into parliament on a budget day without it.
To mark the day, the Treasury boss would raise it and wave to the flashing cameras before matching into the August house to announce how the government plans to spend that year's budget. It is these iconic photos that identify former ministers at the Treasury boardroom.
The black briefcase was expected to lose its significance after the new constitution was passed in 2010. This is because most of the information in the budget should have been presented to parliament long before the statement is read.
So this takes away the significance of Budget Day reading because what Kenyans wait to hear is just the tax measures. Never the less, the tradition lives on.
Though it is now more ceremonial than what it was previously, the Briefcase still remains a key accessory to the Treasury chief when he walked into parliament buildings.
Days before a budget is read, an employee of the national Treasury walks into the cabinet secretaries office to pick the briefcase from where it is kept. His job is to service it and make it ready for the big day.
The employee makes sure the locks are working properly, then he makes it ready for the budget statement. It carries nothing else but the budget statement.
This tradition has been passed on year after year because of the briefcase used to carry the 'big secret' in the budget and Treasury always wanted no one to take the thunder away from the cabinet secretary.
The briefcase has a special code and myth has it that it would electrocute you if you tried to open it without the password.
"I have also heard that it could electrocute you but no one has ever suffered that. I also do not know where it is kept, it is probably kept in the Cabinet Secretary's office," Treasury Principal Secretary Kamau Thugge.
The code is only known to the cabinet secretary and a few other handlers.
Kenya inherited the tradition of carrying briefcase from the colonial government.
The briefcase was first waved to Kenyans at the then new parliament that is now occupied by the Bank of India on Nairobi's Kenyatta Avenue. At the time this road was known as the Delamere Avenue.
The history of the briefcase stretches back to 1860, when then Britain's budget chief, William E. Gladstone, needed something to carry the massive load of documents he had to walk down to the House of Commons.
It was a lot of paper, as such speeches had been known to last hours. The original budget box was made: 14½ by 10 inches, wooden, lined in black satin and covered with red leather, brass hinges.
But this is a little too big today because the budget speech now has less pages that would perfectly fit in an A4 envelope. But as tradition would have it, these too must be carried in the famous briefcase.
When Amos Kimunya was in office, the briefcase became a little too old and had to be replaced.
"I am not sure how much it costed. It has been replaced either once or twice. Most people with the institutional memory on the briefcase have left," a source at the National Treasury said.