help with my viair 380.....

ok i bought a 380 from a friend. its braided hose had a 1/4" fitting on it. i bought a new 380 later its neither 1/4" or 3/8" its in between. it came with 3/8 line but it wont fit in either of my sd 1/4" and 3/8" reducing bushings what can i do. do they make 5/16" fittings?

thanks...