These push-on crimp Connectors are gold plated for better anti corrosive contact.
These are sold in pairs and come with their clear silicone insulation boots so you have enough for one loudspeaker driver unit per purchase.
The type of insulation cover supplied with these is superior to the integrated boot or more often seen with this type of connector as it gives the option for soldering and for better mechanical contact when crimping.
These gold-plated push-on connectors to fit 6.3, 4.7 or 2.8mm spades, ideal for use on drive units, thus avoiding the need to solder directly to the drive unit terminals and the damage that can be cause by to much heat.
They can be soldered or crimped (or both).
The 6.3mm connector is designed for 2.5mm cable it is possible to fit 4mm cable but depending on the cable outer diameter you may find that some brands may not fit. If you are soldering that shouldn’t be a problem.
The 4.7mm connector is designed for 1.5 mm cable.
The 2.8mm connector is designed for 1 mm cable.