Costco Model #: 790842
B A C K - I N - M O T I O N ™ M I D B A C K C H A I R
A.
Remove all parts from carton and separate them into part number groups as indicated in parts list.
B.
To begin assembly, place 5 Star Base (2) upside down and insert Casters (1) into bottom of Base (2).
C.
Turn Base (2) right side up on the floor and insert Gas Lift (3) into center hole on Base (2).
D.
Place Telescoping Cover (4) over the Gas Lift (3) and rest it on the Base (2).
E.
Align the Lumbar Cushion (8) with the Seat Cushion (7) by positioning the Lumbar Cushion (8) between the Seat Cushion (7)
and the Back Support Plate (10), attach by using 1” Small Screws (14) as shown in Diagram 1.
Tighten screws completely.
F.
Attach Seat Plate (5) to the bottom of the Seat Cushion (7) (with the FRONT of seat plate facing the FRONT of seat cushion).
Attach by using 1-1/4” Big Screws (12) for the front holes of the Seat Plate (5) and 1” Big Screws (13) for the rear holes of the
Seat Plate (5) as shown in Diagram 2.
Tighten screws completely.
G.
Align Handles (H1 & H2) of Seat Plate (5) over pre-drilled holes on the left and right on the underside of Seat Cushion (7),
attach the Handles (H1 & H2) to both sides of Seat Cushion (7) by using 1” Small Screws (14) as shown in Diagram 3.
Tighten
the screws completely. Fix the cable for the seat plate into the plastic clips attached to the bottom of the seat
cushion.
H.
Attach the Arms (6A & 6B) to the bottom of the Seat Cushion (7) (with the FRONT of arms facing the FRONT of seat cushion)
by using 1” Small Screws (14) in the arm holes as shown in Diagram 4.
Tighten screws completely.
I.
Attach the Back Support Plate (11) to the Seat Cushion (7) using 1-1/4” Big Screws (12) as shown in Diagram 5 and t
ighten
screws.
J.
Place the assembled chair on top of Gas Lift (3) and press down until fully engaged.
K.
Periodically (every 90 days) make sure that the screws are still fully tightened.
ATTENTION: Be certain that all screws are fully tightened before using chair.
Part # Description
Quantity
1.
2.
3.
4.
5.
6A.
6B.
7.
8.
9.
10.
11.
12.
13.
14.
15.
H1.
H2.
Casters
5 Star Base
Gas Lift
Telescoping Cover
Seat Plate
Left Arm
Right Arm
Seat Cushion
Lumbar Cushion
Back Cushion
Back Support Plate(already
attached to the seat cushion)
Back Support Plate(already
attached to the back cushion)
1-1/4” Big Screws
1” Big Screws
1” Small Screws
Allen Keys
Right Handle
Left Handle
5
1
1
1
1
1
1
1
1
1
1
1
6
2
15
2
1
1
A S S E M B L Y I N S T
R U C T
I O N S
P A R T S L I S T
