Polished solid brass silencer adaptor with muzzle brake. 

Adaptors slip on 40mm and are secured via x2 M4 grub screws.

10mm (with a taper to 12mm) compatible with Air Arms S400/410 

  11.05mm compatible with Crosman 2240/2250  

14mm compatible with early SMK XS78 

14.5mm Compatible with SMK XS501

 15mm Compatible with SMK QB78/TH78D and AIR ARMS S200 MK3 

Adaptors will also fit other makes and models not listed.