From the instructions here: http://www.aerotech-rocketry.com/uploads/d8bbe5c9-11ef-4cd9-8457-1c87da6917d0_54_2560nw_bs_in_20072-2.pdf You can use either the standard regular length or the plugged regular length forward closure. From: Scott Christiansen <scootdawg30@xxxxxxxxxxx> > Subject: [roc-chat] K375NW > Date: Thu, 25 Oct 2012 15:33:20 -0700 > > > > > Does the K375NW require an end burning fwd. closure, or will a standard > plugged one work? > > >