Yes, the H16 main halyard has 2 nicopress sleeves attached to the wire....
the 2nd slug is the one used to secure the sail when it is hoisted using the main halyard hook attached to the leading or forward edge of the mast....
http://www.murrays.com/mm…e=25-3330&Category_Code=
the 1st slug is used to reef the main in an emergency situation thereby reducing sail area.
Clean track and then eyeball to see if track is "pinched" anywhere along the length, dropping the mast is the biggest cause of pinched track, if pinched, obtain round dowel same diameter of track and slide it up the track to pinched area, use force to move dowel through pinched area to open it up. Insert main sail into track and check to see if it slides freely up and down track, also make sure that 2nd stopper reaches the hook, fine tune if necessary untill sail slides free.
Next check mast head sheave, made of nylon(?) and subject to deterioration by uv, make sure sheave rolls freely and slugs pass over sheave without binding, its a hassle when raising sail and halyard jumps off sheave and slug binds between masthead and sheave, you have to capsize boat to get to masthead, replace sheave if in poor condition.
When raising the sail on the H16, pull main halyard at a 45 degree angle to the mast, when the headboard hits the top of the mast, bring halyard in towards the mast and insert stopper on halyard into the "V" of the halyard hook, drop slide of goose-neck on the boom into sail track and crank on down-haul, this will keep tension on main halyard ensuring that slug does not jump out of hook. Coil tail of main halyard and stow in pocket on tramp, if no pocket, use velcro strap to attach to mast or wedge between down-haul line on mast.