The diameter is φ114mm/4.49".

Yes, the Gnosis series are available in a single hard case set and 3-lens hard case set.

1. Red number corresponds to MAG-Magnification. That is, at this focusing distance, the ratio of the in-focus object on the imaging screen to the actual size.
2. The green number corresponds to EXP-Exposure Compensation. Due to the special optical structure of the macro lens, the actual T value will be different from the T value indicated by the current aperture ring during macro shooting, and the exposure balance needs to be adjusted according to the value indicated by EXP.
For example, under the aperture T2.8, the EXP value is "+3", then the actual T value is equal to the current aperture T value plus 3, which is T5.8.

The lenses are available in metric and imperial versions, both in black color.

The main difference between the two is the appearance structure. Gnosis’s 114mm diameter is more common in the rental industry and professional film and television creation. Therefore, in this scene usage habits, its versatility is higher than Vespid, and Vespid is suitable for Users who have requirements for volume and weight control. In addition, the Gnosis series has one more LPL mount than the Vespid series.

For the mount changing, please check out below Tutorial:
https://www.dzofilm.com/support/lens-tutorial/738.html
Please noted that the suggested torque is 0.4Nm.