Filter is not sticker. Its something like 1 cap that screw with your lens. Usually lots of user are on Kenko and Hoya. I have no idea bout others? If 52mm I guess is around RM80-90. And usually stick on the lens for 24 hours is the UV filter.
Correct me if something i say wrong. =)

Not stick on the surface, its screw on the lens. UV filter is usually to protect the lens and also block UV ligthing. Effect of UV just a bit, not much effect. There is few type of filter, which is ND, CPL & etc... But there is some others ppl will prefer naked, dont put any filter liked our bro JLOI here.

Filter look like this,

http://www.letsgodigital.org/images/artike...lens-filter.jpg

I believe filter can get from some forumers here too.

Bro, that is example how filter look like.

You just need to go to the shop and told them you need filter. And get the brand & size of the filter you want. If dont know, just bring the lens to the shop and told them you want the filter for that lens.

just bought gx1 last few days.. so far quite satisfied
the only problem is i noticed quite a lot of hot pixel, how many is considered as acceptable? should i return it?

afraid i bought a lemon set,
at first, i asked for a new sealed set but the seller insisted that thr is no demo set and the one i am holding is new.. so i gave up
besides, i am always a loser when trying to ask seller for 1-1 exchange.. can give some tips how/what to say?
spent my hard saved money and found out that stuck pixels is all over the place.. 

here is what i meant


hotpixel is visible even at lowest iso with 2 second exposure, anyone out there can test ? just want to check whether my toy is normal or lemon
@sinner

the method i use is use lens cap, then shooting raw with manual with few different ISO and shutter speed
eg.. ISO160/800/3200 @ 1 second, 10 second, 1/5second ....