Hikvision's HIK-KB8113-IME1 is the stainless steel version of the single button modular door station which is specifically designed for the IP range, therefore making it great for retrofitting existing sites.
The anti-vandal version is made from zinc alloy material that can be mounted in 12 different positions in 7.5 degree increments, covering a range of 90 degrees. Being able to withstand harsher than normal conditions, such as weathered environments or physical tampering, it makes for the ideal intercom for high risk circumstances.