b'Fly BlocksFly BlocksHarken soft-attach Fly blocks are designed to provide strength without mass, providing sailors with big power in a low-aero package. Designed specifically for high-tech line, these efficient blocks have an incredible working load for their small size. Fly blocks are perfect for use on foiling dinghies and sportboats and for vang cascades and backstay systems on Grand-Prix racers.18 mm18 mm blocks feature an integrated stainless steel inner race and rivet, stainless steel ball bearings, and composite fiber-reinforced sideplates.29 & 40 mm29 and 40 mm blocks feature a one-piece titanium outer race/sheave, stainless steel ball bearings and inner race, and composite fiber-reinforced sideplates.Use the 2161 tight cinching 18 mm in applications where the block needs to be secured extremely close to the deck. 2161 2698 2158 2180 2171 2173Sheave Max line Maximum BreakingPartLength Weight working load loa dN o. Description in mm in mm oz g in mm lb kg lb kg215818 mm Double23/32181 3/32 61754502041500680 28. 3/16 216118 mm Single/narrow23/32181 3/3228.253/165275125992450 7.2 . 9/321540700 217129 mm Single * 1 1/8291 3/444 92267770350 217340 mm Single * 1 9/16402 5/165862.211/32143565028701300 2.29 218018 mm Triple23/32181 3/3228128.456002721100499 3/16 269823/32181 3/3228.257.23/165125992450 18 mm Single275 16 *Lashing line not included.'