"Sixty-eight is too late" reads the slogan behind the stage in Methodist Central Hall where union leaders have been addressing the ranks of public sector workers who converged on Westminster to voice their anger over the government's planned changes to their pensions.
After speaking to many of those who came for this rally, it's clear that this is perhaps the most controversial part of the government's pension reforms.
The plan would see the payment of the public sector worker's occupational pensions linked to the age at which the state pension is paid, which is set to rise to 68. It's an issue which raises the blood pressure of those marchers I have spoken to.
As he carried a banner across Westminster Bridge, Martin Powell-Davis told me "public sector workers - whether they are in hospitals or schools or anywhere else - cannot work at the kind of pace we are asked to work at until the age of 68".
"People know that we will be asked to work until we drop - and we won't get a pension because we won't live that long."
Another marcher, Kate Paton - part of the National Union of Teachers (NUT) delegation which came to back the strikers on Thursday (the NUT is not on strike) - told me "No-one wants to see teachers and health workers doing the job at 68 when we need to make way for younger people."
The question is particularly acute for those like hospital porters or MoD police officers and firefighters who have jobs which can be very physically demanding.
Without exception, those I spoke to said the strength of feeling on this issue alone would mean there would be support for more and deeper strikes.
That said, it's clear that this action has caused far less disruption than the November strike.
Hundreds, not thousands attended this rally, fewer front-line services and fewer people were affected than in November.
More action is planned for the end of June and this time the teachers' unions are considering going on strike too.
It was their decision to join the November strike that caused probably the greatest disruption as parents were forced to make other plans for their children including taking the day off work.
The NUT executive is due to meet this month to discuss what role their members should play in any future action.
The tone of many of the speeches here was that public sector pensions is an issue that all unions should now be united over.
Mark Serwotka, general secretary of the Public and Commercial Services Union (PCS) said he would ask the TUC leadership next week to throw its support behind the campaign to force the government to reopen negotiations.
This then is a key moment for public sector workers as they assess how much pressure they can realistically apply on the government and whether there are any signs of cracks in the position held by ministers - that the negotiations are over and there is no more money in the pot.
So far, statements about the "futility" of the strike from Cabinet Office minister Francis Maude suggest that they are not in a mood for further talks.
But the sight of prison officers taking action and a huge march by off-duty police officers through Westminster may give them pause for thought, especially as the PCS and Unite gather support for what they hope will be a more wide-ranging strike in June.