Air intake pipe diameter

[Eirebhoy232]

Hi wondering if anybody could help me out, Bought my blobeye with a small crap eBay induction cone so I bought a second hand replacement but the pipe isn’t fitting mine just wondering if anybody would know what size silicone pipe il need or could measure it for me as my mechanic is currently busy with family matters and I don’t want to bother him over a silicone pipe at the moment and I dont live close enough to go measure it myself. 

thanks in advance and very much appreciated