refractometer questions

[gogol]

I am thinking of getting a refractometer off of ebay. There are some that require a mini screw driver for adjustment, and some that use a knob. I am inclined towards the ones with the screw sriver, because if things are jammed, it would be easier to maneuver. Is there any reason to think otherwise?

I know that some of how have purchased the refractometer off of ebay, any seller I should stay away from ?

Thanks
Gogol

 

[dangerbird]

I don't think it matters much, but I have the screw type and it works fine. I only use it like once a month so it's not like it gets bounced around a lot. And they are easy to calibrate.

 

[NJ_ychung1]

me too. screw type. was like 40 buckaroos at dr.fosters internet site. works fine.... easy to use and cheap.

 

[rgarofalo]

the nice thing about the screw over the knob is that it is easy to bump a knob and throw it off where the screw is recessed

 

[ricwilli]

I've used the one with a screw and never had a problem.