This standard specifies the connection tools or bare crimp sleeves specified in JIS C 9711 (Wire connection tools for indoor wiring) to connect stranded or solid annealed copper wires used primarily for equipment wiring and indoor wiring. This specification specifies bare crimp sleeves (hereinafter referred to as sleeves) in which wires are crimped and connected using a connecting tool (hereinafter referred to as tools) (1) specified by the manufacturer. Note (1) Use a bare crimp terminal tool to connect linear butt sleeves and linear overlapping sleeves, and a manual one-handed ring sleeve tool to connect terminal overlapping sleeves.