Throughout both World Wars, most Mills Bomb type grenades came in stout wooden boxes that contained 12 grenades and a tin of detonators. These boxes were cheap and reasonably robust, but were not suited for all circumstances. The boxes were not particularly waterproof and were unsuitable to be airdropped. It was therefore decided that metal ammunition boxes would be used for some grenades to counter these problems, however it was necessary to develop further packaging as it was obviously not suitable to have the grenades rolling loose in a metal box.
The solution was a cardboard tube, much like that adopted for the 2″ mortar bombs, that could carry three grenades and a tin of detonators securely, that could then be carried within the metal ammunition box. These tubes are exceptionally rare now and today we are looking at a post war example:

The tube is made of stout cardboard, with a pair of reinforcing rings about 2″ from either end. A removable tin lid is fitted to one end:

Removed, this allows the Mills bombs to be slid into the tube:

A metal end piece is permanently attached to the opposite end:

The tube has a plethora of markings stencilled on. At one end is the warning that the contents are explosive:

The main tube is stencilled on both sides. One side has details about the tube itself which was manufactured in 1956 and has the stores’ code SV71A:

The tube has clearly been repainted at some time as the paint goes around this marking, leaving a little patch. The opposite side of the tube details the contents:

From this we can see that it contained three No 36M grenades and 3 detonators for the same. The detonators were the Mk 8 pattern and each had a four second delay. The grenades were manufactured in April 1972 and the detonators were produced by ICI in February 1972.
This tube is a scarce survivor and is back doing what it was designed to do: holding the Mills Bombs in my collection nice and securely.