Stargazer swimmer fly.
Flexible foam, floating / subsurface swimming style fly.  Designed to swim at or below the surface.  Depending on the type of retrieve. Strip retrieve for quick jerky, darting movements or a constant (two-handed) retrieve for wobbling swim.
Hook size:
#4 - 1 5/8” L foam body
#2 - 1 7/8” L foam body 
1/0 - 2 1/16” L foam body