Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: for how long or how many times should it be used without changing the filter and how to change it ?
Document: I had always used compressed air cans to clean out my computers. They didn't last all that long, weren't all that powerful and couldn't be continuously used without losing what little pressure they had. I then tried an actual vacuum (produced by the same company actually, Datavac) but it wasn't very efficient at getting in all the places I wanted it to. It was also a pain in the neck to have to constantly change the attachments to get different spots cleaned.
Not a vac, but a pint-sized (or maybe a little larger) blower. Perfect for blowing out computer cases. I've already said it too many times to my friends - but it is one of the best purchases I've made in a long time. No complaints at all! I even have used it to blow out the filters on my air purifier. No more cans of air - no more hassles. Great stuff!
Although it has uses, canned air just doesn't last very long.I've helped some friends out with computer issues, and many times I think the initial cause was just dirt covering everything in the case! Components overheat and/or short out in a dirty environment. This blower is small, very portable, and very powerful. I wish I had it sooner. And yes, if you don't want a bigger mess, blow the case out outside...
Not to be used in a quiet room, except with a extention hose kit.But very very powerful.Fast delivery, Thanks many times.
This blower completely blows them away. (lol) It really is like a mini leaf blower, can move a serious amount of air in a large or concentrated area depending on what your need is. Had for a little over a month and used it multiple times. Foam filter at bottom is great for catching dust. One thing not noted in manual tho... the filter you just kinda squeeze and pull out to clean and put back in but it does not explain this.
This has been a very useful device! I dust our ~10 computers every few months, and that used to take a lot of Dust-It&#8482; cans (all that propellant, all those empty cans into landfill, or even to recycling). By now (after couple of years of use) this unit has paid itself back many times over.
Very powerful (loud) but so many usesObviously cleaned my PC with ease but i've also used it for:-Cleaning my Dyson style Shark Vacuum and filters-Blowing out debris from behind/under areas like refrigerator that i didn't feel like moving-Strong enough to blow the leaves off my front porch when i didn't want to get out the big blowerLong cord lets you wander a bit and great assortment of attachments for different jobsNever buying canned air (dust off) againLoud but can still use indoors without issue
This thing is great. I do many iPhone/iPad repairs and used to buy the cans of compressed air to ensure that &#34;No Dust&#34; was on the screen before sealing the unit up. This DataVac has a filter to ensure the air used to clean is free of debris. The cost of the compressed air cans used in a few months is much higher than the price for this datavac. Very glad I bought this item.
This device is a bit loud, but it is quite powerful and can be used to clean the inside of computers very well. As someone who does regular cleaning of PCs (several times per month) I was tired of constantly buying canned air to do the job. The power cord on this duster is long enough to give one plenty of room to work with and the force of air expelled is great for dusting components.
There are different attachments that come with it and are precise for the jobs you need to do. The casing is heavy duty, not cheap, thin metal.There's a 5 year warranty on the  motor. ( Imagine that! ) The filter is easily accessible to change out.It has a nice heft to it but it's not heavy or clumsy to use. And i got it super fast. And no i don't work for the company.
Answer: Honestly it seems like every time you use it the filter gathers dust and you just wipe it off with your hand *Think lint brush here*.As soon as it's clean you're done. in terms of replacing it. Hmmm who knows...seems like it should hold up for quite a long time. If not you can replace it for like $5 on their website or make your own.