Their protest is designed to call attention to the decision by the MOD’s Defence Equipment and Support organisation to deny a retention allowance to scores of workers at DE&S Caversfield, Bicester.
Key technologists and support staff who design protective clothing and equipment for the armed forces stand to lose between £3,000 to £9,000 a year as a result.
Originally the allowance, intended to retain skills at the site in the run-up to its relocation to Bath in 2009, was to be paid to all 170 staff. But early this week, central DE&S management in Andover informed Caversfield that it would only be paid to one third of employees.
George Clarke, Prospect section secretary at Caversfield, said: "These are key workers, doing a vital job for our armed forces in the front line. They are already being relocated against their will and now they are being financially messed around in a disgraceful manner.
"Members are absolutely furious – I have never known such feeling at the site. Management must return to the negotiating table and frame a new offer, whatever the limits on affordability."
Otherwise, he feared specialist staff would leave the site in droves, doing long-term damage to the business and to standards of protection for the armed forces.
Among equipment designed at Caversfield for personnel in Iraq and Afghanistan is desert kit, body armour, boots, body coolers, safety spectacles and much else.
The meeting of Prospect and PCS members will take place at DE&S, the Ring Road Roundabout, Buckingham Road, Caversfield, between 1pm-2pm.