Hisense 3 Series User's Operation Manual page 24

Important: Transport bolts which are not removed can cause damage to the
appliance.
Screw off all transportation bolts for approx. 30mm with wrench following the
direction of arrow shown (not fully screw it off).
Push four transportation bolts on horizontal direction inward and
loose transportation bolt.
Pull out transportation bolt together with rubber part and plastic part.
To ensure safety and reduce noise, you should install the transportation bolt
cover supplied with the unit (see the annex accompanying the unit). Lean
and place the transportation bolt into hole and press it following the shown
direction until it clicks.
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