To check the correct size for a LightRider Bitless Bridle, please take the following measurements:

1: Around the nose (3-4 fingers below the cheekbones
– as shown at 1a).
2: Over the poll (head) from each side of the noseband.

LightRider Bitless Noseband
Mini: up to 35cm (13.5”)
Pony: 41-56cm (16-22")
Cob: 52-60cm (20-24")
Full: 56-66cm (22-26")
W'blood/Draft: 64-77cm (25-30")

English/Stockhorse/Western Styles
Cob: Nose 52-62cm (20.5-24"), Head 73-100cm (28.5-39")
Full: Nose 56-66cm (21.5-26"), Head 96-106cm (37.5-45.5")
W'Blood/Draft: Nose 65-74cm (25-29"), Head 100-122cm (39-48")

Rope Styles - Natural & Performer
Mini: Nose 33-39cm (13-15"), Head 65-75cm (25-29")
Small Pony: Nose 40-45cm (15-17") Head 70-80cm (27-31")
Pony: Nose 45-50cm (17-19"), Head 80-90cm (31-35")
Cob: Nose 50-55cm (19-21"), Head 88-108cm (34-42")
Full: Nose 54-63cm (21-24"), Head 96-112cm (37-44")
W'Blood/Draft: Nose 63-72cm (24-28") Head 106-130cm (36-51")

The bridles will generally fit the following heights unless they have a larger than usual head: 

Mini: Under 9hh (90cm)
Small Pony: 9-11.2hh (90-117cm)
Pony:11-13.2hh (112-137cm)
Cob: 13.2-14.3hh (137cm to 150cm)
Full:15-17hh (152cm to 173cm)
Warmblood/draft: solid 17-18hh (164cm to 183cm)