been using fleece tights & Novara cycling pants for cold rides but I think my 58yr old left knee would benefit from another layer. left knee probably has a touch of arthritis or tendinitis that acts up in these long duration cold situations

thinking about knee warmers but don't want something tight. also not sure where I would wear it, next to skin? over fleece tights & under cycling pants? (there isn't much room) or over the cycling pants? (this would be easier to add during the ride but should be black to blend in, thick & fleecy but wind proof?)

if I keep the rides to under 2.5-3 hrs I might be OK without but would like something I cold maybe throw on after an hour or two, when I know I'll be out for a bit more time