This is the Alunar Pneumatic Damper, an antivibration passive system made for Infitary Printer known as Alunar mini R100. The concept of this system is represented in the 2th picture.
It's so much important to print the damper as reported in the Print Settings below.
This is the second accessory made for Alunar mini R100, for more info read the post on my personal blog.

Alunar mini R100

No

No

0.2

110%

version = 1
name = Alunar - BQ Pneumatic Damper
definition = fdmprinter

[metadata]
quality_type = normal
type = quality_changes

[values]
bottom_layers = 0
infill_pattern = zigzag
magic_spiralize = True
top_layers = 0
layer_height = 0.2
speed_slowdown_layers = 1.0
material_print_temperature = 195
material_diameter = 1.7
material_flow = 110