Delrin Slick Regular Guitar Picks (24 picks) Medium. Fred Kelly's Slick Pick has a flat pick point that enhances smooth strumming. This pick is neither big or bulky and is the first pick of its kind that behaves like a flat pick. The Slick pick is available in delrin or polycarb materials. Delrin is an extremely strong material, and provides a soft and natural sound on the strings. 24 to a bag, choose gauge.