From Ola Onsrud's youtube video description:
A video shoving how to dress in and wear armor (harness) from late 14th century. The harness is a detailed reconstruction based on the effigy of the Black Prince (1330-1376) in the Canterbury Cathedral, other relevant effigies, paintings in 14th century manuscripts and late 14th century armour displayed in The Royal Armories in Leeds.
From his facebook page:
Those who have participated in the reconstruction of the harness are:
Basinet and breastplate made by Albert Collins (via armorari)
Sabatons, plate legs and gaunlets made by Russell Thomas
Plate arms Roman TereschenkoKnight belt and necklace made by Jakub Vácha / Klinštejn ShopMail supplied by GETDRESSEDFORBATTLE© (gdfb.co.uk)
Sword form Albion Swords Limited LLCFittings for belts and scabbard from Tods StuffI (Ola Onsrud) have done all customizing of the mail, made all textile/clothing and leatherworks.
He's got a video on 14th C target practice and one on 13th C armour, that goes over how he made and modified some of the pieces.