While water-based lubricants (for example, astroglide) are the most commonly recommended type of lubrication, many people like silicone-based lubricants (for example, Wet). Silicone-based lube lasts longer, is still effective in water and you need less of it. In addition, there are some data that silicone-based lubricants are less irritating to the rectal mucosa (i.e. the butt), and that people who use silicone-based lube are less likely to get rectal STDs than those who use water-based lube. Oil-based lubricants (e.g. petroleum jelly) are not safe to use with latex condoms, as they cause the condom to break. If you are having sex with a condom and want to use an oil-based lubricant, you should use a polyurethrane condom.