Seco Tools India [P] Ltd. Offers Polycrystalline Cubic Boron Nitride Inserts with C-lock Hole. Seco Tools India [P] Ltd is an ISO 9001 and ISO 14001 certified company. The Polycrystalline Cubic Boron Nitride Inserts with C-lock Hole works against the current tipped concept. In these inserts, a full faced PCBN layer runs across the top of the insert, depths of cut are no longer limited by tip size and with no braze joints or PCBN pockets, the cutting edge will never be lost to braze failure.