As its a front & back would I need 2?
It only takes one, the front and rear video files go on the same card.
It is good to have a spare in the car, so that if you capture something very important, it is easy to put it somewhere safe, where it can't get overwritten. The spare can be a very small one.
was wondering what size sd card
That is really up to you, some people only want to keep a few minutes of video before it gets overwritten (that is the law in Germany), others want to keep a whole day, so that they can download important stuff at the end of the day, some people want to keep a whole week.
In general, larger cards will wear out slower, so a big card is an investment rather than a waste of money.
For a 2 channel A229 plus, the popular sizes are 128GB or 256GB. A 64GB is usable, but it will have half the life of a 128GB, and it won't always keep files for a full day.
Also is there a certain class I should go for?
Class isn't too important, heat resistance is more important.
Viofo have a page of guidelines and recommendations, note the ones they recommend against!
(Generally because of poor heat tolerance.)
Micro SD Cards play an important role in dashcams, but not all cards are suitable to be used in dashcams. The footage recorded by dash cams is saved on a micro SD card, which is an essential component of the dash cam setup. Here are some parame...
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