From my steel Monark five bar, this seatpost and shim are unique. Sold together. Quill steel seatpost is 7 1/4” long, 5/8” diameter at top, and 13/16” below. The shim has 27/32” interior dia, 28/32 exterior, and 2 15/32” long. $50 plus shipping from northern CO. Cash and carry or PayPal.