They were then pushed into a freezer.
A backpack containing the wallet, drivers licence and passport and cellphone of one of the staff was also stolen.
The men then ran out of the backdoor towards Lynn Mall.
The staff managed to open the freezer door from the inside several minutes later and called Police.
Both staff members sustained minor injuries and were severely shaken.
The incident was the 8th aggravated robbery of a retail outlet in New Lynn since June and investigations into whether they are linked are underway.
The previous 7 robberies have taken place on the following dates and locations;
7 June - Radius Pharmacy Delta Avenue
18 June - Radius Pharmacy Delta Avenue
6 July - Hells Pizza Totara Avenue
10 July - Mid West Pharmacy Great North Road
10 July - Radius Pharmacy Delta Avenue
23 July - Hells Pizza Totara Avenue
9 September - Subway Great North Road
POlice say they are investigating whether these crimes are being done by the same people.
"The first 7 robberies were committed by one offender who made no attempt to hide his face. Thursday night's robbery was different in that there were 3 people who did disguise themselves," Detective Sergeant Steven Salton, Henderson CIB said.
"One of our biggest concerns is that this latest attack had an escalation in the level of violence used and we want to stop whoever is responsible before someone gets seriously injured"
Six of the robberies have taken place between 5 -7 o'clock in the evening.
"Whoever is doing these crimes is armed and aggressive in places where you could quite easily expect members of the pubic to walk in. In several of the robberies it's the second time the shop has been targeted and the same staff members have been re-traumatised."
In the first 7 robberies staff have been physically pushed, grabbed and threatened by a lone man with a gun or a screwdriver. The offender has threatened them and demanded money.
"It is highly likely that someone out there knows who these people are. The people that work in these shops are simply trying to make a living and I cannot reiterate how important it is that these offenders are stopped before someone does get seriously hurt" says Mr Salton.
Anyone with information is asked to call the Henderson Police on 09 8390600 or to report it anonymously to Crimestoppers on 0800 555 111.