Olight S15 Baton w/additional battery tube
From: andrew-amanda ebay store (Flashlight-Scope-Outdoors)
Sellers website: www.andrew-amanda.com
Great price from US seller (less than Chinese sellers!) and arrived very fast (3 days!)
Considerably smaller than my Olight S20, although the head is exactly the same size.
Also have a 3rd battery tube on order to allow use with 3xAA
More info/photos here