LifeSpan SP-850 Owner's Manual page 7

a. Secure the saddle post join (3) to the main frame (26) with L shape locking
bar (36).
b. Secure the saddle post (2) to the saddle post join (3) with knob (5) and
washer (4).
C. Secure the saddle (1) to the saddle post (2).
Step 3: