Hi this is the info I got from eBay
The Keeper 'Type 2' - Engineer Boots
Last : Kapak
Size: 43 (to be confirm)
Upper: Natural Oiled Horsebutt overdyed Brown
Lining : Tan Halflined
Midsole : Single
Outsole : Dr Sole Black Supergrip
Halfsole
Welt Color : Antique Brown Edge Color: Antique Brown
Welt Stitch: White
Construction : Flatwelt 270°
Toebox: Unstructured
Heels : Woodsman Heels
Elastic: Raw Brass
09:39
Here is the specification
Email from Briselblack
Hi Daniel,
Thank you so much for your kind words, it truly means a lot to us. We’re grateful to hear that the fit works better for you.
Regarding the leather, from the photo it appears to be Oiled Horsebutt from Shinki Hikkaku tannery, at 2.3 - 2.5mm thickness.
Once again, thank you for the support,
Warm Regards,
Adi
Briselblack Bootmaker