Filter size for Canon 50mm 2.8 lens

[guangong]

Just purchased a "Canon lens 50mm f2.8 serial #128**" and want to get a few filters. Lens came with Minolta uv filter without size designation so no help there. Don't know if this lens takes same size as 50mm 2.8 seranar. Lens is like new. So much appreciated if anybody has this lens and can give me the correct screw in filter size!
For my Canon P, didn't want to chance any of my Leica collapsible lenses because I know that I some time I would push lens into body. My ltm f1.5 is too big and not needed for this camera.

 

[kb244]

Does it look like any of the ones here?

http://global.canon/en/c-museum/series_search.html?t=lens&s=s&s2=standard

Two say 40mm, the 1955 version says 34mm.

 

[monst]

you could measure it with a ruler for a ball park figure

 

[guangong]

Thanks kb244, for info on the canon site. My lense takes the 34mm filter. On the other hand "no thanks" because you have just led me to another site where I will waste my time instead of doing something useful. Just kidding. Thanks again.