Wimberley WH-200 Version II brand_Pentacon and it's compatible with a

and it's compatible with a huge number of excellent lenses

The Vivitar A35 is "Splash Proof" but

The Canon EF 300mm f4L USM is a high quality telephoto lens with quick USM focusing and Canon's premium L glass and construction

This is a heck of a lens

Includes a threaded flange for mounting to a lens board (not included)

Wimberley WH-200 Version II brand_Pentacon and it's compatible with aThe Wimberley WH 200 Version II is a solid, professional gimbal head designed for long telephoto lenses: it'll hold up to 45kg, which should be enough for almost anything. In excellent condition, with minor cosmetic wear. Locks are excellent, and movements are smooth. The integral clamp is Arca compatible; a Wimberley P40 plate is included. Heck of a head.