Fifty Shades Darker has caused this sex toy to sell out

It used to be niche...

NSFW alert (in case you needed it.)

Sex toys for couples have been around for years but some are definitely less common than others. A cock ring is considered standard these days. A remote control vibrator? Common game, now, apparently. Heck, there are even penis expander accessories (aka sexessories) to help really, um, fill you up should you need it.

And, don't even get us started on how everyone seems to be talking about jiggle balls, too. We're also thanking Fifty Shades Darker for that one.

But what you may not already have in your standard sex routine repertoire (or should that be, drawer) is probably a spreader bar.

Yep, here's a picture of spreader bar so you can really get it. They pretty much do what they say on the tin. And if you haven't seen the film yet, they're a big feature in a specific scene, FYI.

And yes, these did in fact sell out on Valentine’s Day - at Ann Summers, any way. The store experienced a 110% increase in sales of spreader bar, alongside a 120% increase in sales of handcuffs.

It's taken such a hit that they've had to ship in extra stock just to meet the demand, so it might be time you get that bondage for beginners article out...

But anyway, back to the spreader bar.

What is a spreader bar?

To put it simply, it's a metal bar with detachable cuffs at the end, which you can fasten onto your wrists, ankles or knees to hold them apart.

It's to make sure you can't close your arms/legs during foreplay.

It's a pretty advanced restraint, mind, so it's recommended you follow the 'two finger rule' which makes sure you don't restrict any blood flow around the area restrained by ensuring you leave enough space.

Yep. It's not for the faint-hearted (or ticklish of us).