I bought my girlfriend a tikka t3 in .270 and a Nikon pro staff 5 2.5x10....

https://www.midwayusa.com/product/3...0x-40mm-nikoplex-reticle-matte-blemished



I would like to use dnz mount which one do I need?

The low version should work just fine.

Should I get the low or the medium

I have low Talleys on my tikka with monarch 2.5-10x42,
My buddy has dnz lows on his tikka with 2.5-10x 42 viper.