Technical requirements:

1, Base tube specification:

Base tube OD: (  )mm, base tube ID: (  )mm, base tube thickness(   )mm, Base tube length:(   )mm, the plain end in both side: (   )mm;

2, Fin specification:

 Fin OD:(  )mm, fin thickness: (  )mm, fin height: (   )mm, fin distance: (   )mm;

3, Material:

Base tube:GB8163 seamless carbon steel? Seamless stainless steel, 304 316L? Copper tube or others?

Fins: aluminum fin or carbon steel fin or copper fins?

4, Making way:

Base tube: need standard thread or not.

Fins: rolling fins or extruded fins.

5: Pictures for reference.