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Powershot "staple gun" / cable tacker on clearance special, comes with some cable tacks included.
Warning: According to comment below this cannot take regular staple gun staples, only cable tacks.
Bunnings Chatswood NSW, don't know about others.
Now $5. Was $19.50 then $10 (so the tag underneath the one in the picture says)
Looks decent quality.
Description taken from Home Depot (in USA) site:
PRODUCT OVERVIEW
The Powershot 5900 is a light duty plastic wire and cable tacker. The Powershot 5900 shoots easy to load plastic insulated fasteners. The stapler can be used for a variety of applications such as Christmas/Holiday lights, garland or other holiday decorations. It can also be used for installing low voltage wiring for home applications such as computer, telephone, intercom, alarm, security, doorbell, thermostat, and speaker wires.
Manual stapler for Use without a power source
Works with powershot 97-559 staples
4 in. long handle
Weighs just 1.2 lb. for easy carrying
Easy rear loading magazine
Secures low voltage wire ΒΌ in. diameter round or 5/32 in. x 5/16 in. flat wire
bought one long time ago for $5, however, it can only be used with the special staples that comes with it. Not much use at all.