BBG M5 Manuel De Service Et De Maintenance page 18

The intake valve (1.5) and the cylinder pressure spring (1.7) are safety components which prevent
air from entering the hammer before the trigger (1.2) is actuated.
Don't forget to examine these safety parts for damage and, if necessary renew.
- Knock out tensioning sleeve (1.3).
- Remove trigger (1.2).
7. Pressing out steel retainer:
Since the steel retainer bush (7) (C20/S19/C17,5/A20/A17,5/E13,9/E15/E115) is a press-fit in the
cylinder (5) do not force it out unless it requires renewing.
ATTENTION
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