Torchwood stun gun
From Tardis Wiki, the free Doctor Who reference
Torchwood stun guns worked by "shocking" targets who have contact with the muzzle in a similar manner to a taser. It had two settings; one for killing and one for stunning.
Gwen Cooper used one of these guns against her boyfriend Rhys, so that she could take him to the Hub without having to convince him to do it. (TW: End of Days)
The team used the stun guns when investigating the factory exploiting the Cash Cow. (TW: Meat)
Ianto used it on Billy Davies, a hitman working for the The Pharm. (TW: Reset)
On one occasion, Jack Harkness accidentally killed a Histrix when he thought the gun was set to stun. (BBCR: Asylum)