Leica binoculars & the best pocket knives, where? (Frankfurt)

Hi,
i´m expecting visit from friends on Friday 7th and Saturday 8th of October (this weekend!) in Frankfurt.
They are leaving on Sunday, but want to get Leica binoculars and go the best pocket knives (Taschenmesser) store in Frankfurt.
I have no idea where to find this goodies and already searched in the internet but gotten no useful information...
Can someone please help me out with some recommendations about where to buy Leica binoculars and what the store selling the best pocket knives could be?
Thank you so much in advance!!!
Gabriela