Good quality, only drawback is the heat shrink shield will not seal to the smaller gauges (< 18g) of wire. Is close but does not adhere as it will on larger gauge wire.

The solder seal connectors are amazing. The heat shrink spade connectors are great as well.

Heat Shrink Spade Connectors

Excellent product. Works well on vibration prone engine components. We used in conjunction with Wirefy ratcheting crimp tool. Heat shrink covering with adhesive included makes a very solid connection.

I recently added a NMEA 2000 network to my boat to connect the VHF marine radio to the chart plotter, so I needed to hook up the network power cable to the accessory switch used for those devices. The switch, of course, already had connectors attached, so I used these piggyback spade connectors (with the Wirefy crimping tool) to keep the connections at the switch neat and secure. And the adhesive/heat-shrink stuff worked great, even though the wires were thin. I'm very happy that it all worked well on the first try, because that hardly ever happens.