HW95 drop in kit

[Guest]

I have just bought myself a new HW95 and want to fit a Tinbum drop in kit. I see that they come in two different sizes 14mm or 13.8mm. What is this size is it the diameter of the spring guide? Does anyone know what size the new guns are? Thank you 

 

[DualMagMike]

should be the inside spring diameter. contact TBT direct they are supposed to have very good customer service and ask them they might know.