Main valve spring (Harper valve) suitable for the following Daystate air rifles:
Air Ranger (versions under 40ftlb)
Air Wolf (check internals)
Griffin
Huntsman Classic
Huntsman Regal & HR
Huntsman Revere
Mk4
Pulsar
Red Wolf
Renegade
Wolverine
Wolverine 2
Wolverine R

1 version suitable for all power specs (if your rifle uses this valve type!)