PMP DH mtb prototype stem, used and tested by pro downhill rider Marco "Bona" Bonanomi in the early 2000s.

Never went in production, there's only a handful existing in the world.

being a prototype it weights a lot (290 grams!!!!) and has got brand new stainless steel hardware (it had very rusty bolts before..)

Specs:

- fits 1-1/8' forks

- clamps 31.8 bars

- it's 50mm long