Current main halyard is 3/8" (10 mm) New England Endura Braid. Previously same size of Samson Warp Speed. Figured it was worth having a little more security than on the jib and spin halyards which are all 5/16" (8 mm) a mix of Endura Braid and Warp Speed. All have stripped cover and reflect my preference for polyester cover and Spectra/Dyneema single braid core which is easy to splice, holds up well in the sun and becomes 'hairy' when due for replacement.