From The Improbable Island Contestant's Survival Guide, Season 2 Edition.

Implants

Your implant is that big, thing built into your body in awkward places¹⁾. It provides you with additional capabilities - and you're definitely going to need those on the Island.

Implants are free to all contestants, and can be removed at the contestant's request²⁾. Get your implants at the Implant Hut in any outpost! Just look for the hut that says “IMPLANTS.”³⁾

For a list of available implants, see this handy list. Some implants are available at the outset,⁴⁾ while other implants only become available later.

¹⁾

Warranty void if seal is tampered with. No user-serviceable parts inside.

²⁾

Any resulting 'oozing holes' are strictly the contestant's fault.

³⁾

In early Season Two, you had to choose an Implant at the start of your run. At some point, Implants were made opt-in.

⁴⁾

read: to newbies