They look like they both could be tombak but with a difference in the colour of the finish. Sometimes pics can be deceiving and not show the true colour and give a false impression of materials.
I've posted this pic before but here it is again to save you searching through the KVK threads. The top two are tombak, the bottom two are zinc and the one in the middle is brass. Note the varying colours of the finish, they can be very light through to chocolate in colour.
Not much to choose between these two, it depends if you want a lighter or darker one! (Given the choice I would go for the bottom one.)
Looking for LDO marked EK2s and items relating to U-406.....
Good examples Adrian, a nice at a glance explaination
"In all my years as a soldier, I have never seen men fight so hard." - SS Obergruppenfuhrer Wilhelm Bittrich - Arnhem