Diffuser for 26.5 mm head diameter or a simple solut,on

I’m still trying to solve my headlight additction :slight_smile: i ordered for a zoomie:
http://www.aliexpress.com/snapshot/6396561857.html?orderId=65015490420741
not arrived, but not sure about its flood beam. Anyway armytek, skilhunt, olight and fenix tried to solve floodness with diffusers. Could you please advice me diffuser solution for this two:

http://www.batteryjunction.com/jetbeam-hc20-xml2.html
http://www.crelant.com/led-flashlights/headlamp/new-ch10-headlamp-xm-l2-460-lumens-222.html

both have 26.5 mm head diameter, actually jetbeam has rectangular head section but giving same head diameter. Or you may suggest to build own diffuser by using some diy parts and i really appreciate :slight_smile: