Siobhan Patrick, 22, purchased the 'multi-functional' torch on the internet from Singapore.
It had a number of features on it and was described as having a 'fashionable' design.
There was no mention on the packaging about it being a taser or a stun gun.
But before it reached Patrick's home in Holytown, Lanarkshire, it was intercepted by security staff at the Royal Mail's logistics centre in Berkshire and a probe launched.
An investigation revealed it had an illegal stun gun contained in it which could produce one million volts.
A legal police issue taser is only capable of discharging 50,000 volts.
The package was addressed to Patrick and she was arrested by police and charged after they searched her home.
Patrick went on trial at Hamilton Sheriff Court where she was unanimously convicted of purchasing the stun gun in March 2018.
PC Craig Stenhouse, 28, said: "I went to an address in Holytown and when I got there Siobhan Patrick was there.
"We were there because of this torch-like stun gun and it was addressed to her.
"She was suspected of trying to buy that item and we took her to Motherwell police office."
Jurors also heard from firearms expert Alan Henderson who told them he did not believe the torch was a disguised stun gun and that it was simply one of the features of the device.
He added: "This is the most common form of device that I deal with and it is equally at home being a torch device as it is a stun device.
"You regularly see stun guns disguised as something they are not such as a mobile phone which only works as a stun gun and not as a phone.
"With this device, the torch gives a nice light and if you wanted to use it as a stun gun then it is also perfectly usable."
The slightest touch against a target with a stun gun or taser is enough to deliver the charge, either directly on to skin or through clothing and in extreme cases it may cause fatal heart attacks.
Sheriff Douglas Brown deferred sentence on Patrick for reports and continued bail.