... G11, Z11, D11 (Longitudinal seam spiral hose, ball head lap-joint nuts at two ends)Ball joint metal hoses G1, Z1, D1 (Longitudinal ... (Connection of external thread M×1.5 and metal hose ball head lap-joint nuts)Thread connection of flat end faces at ... (Connection of external thread M×1.5 and metal hose ball head lap-joint nuts)Thread connection of flat end faces at ...