Sydney Sweeney kicks back in a bra and boyshorts

Sydney Sweeney is taking under-dressed to a whole new level.

The actress showed off her physique in matching sea foam green bra and boyshorts set from her Syrn underwear brand.

Sweeney posed for steamy snaps wearing the First Base Scoop Neck Bralette ($39) and the Back For More High Rise Boyshort ($16) paired with the Better On You Unisex Wide Leg Pants ($79).

The ensemble is from the new collection, called Small Town Girl, that’s part of a line of “playful” loungewear in the lingerie line.

“are you a small town girl? 🫶🏼 new drop out now @syrn 🩷💚,” she captioned a carousel of snaps of the sultry look.

In another post promoting the new drop, Sweeney danced around in the outfit.

“Doing the launch day dance @sydney_sweeney 💃 Small Town Girl is officially LIVE on SYRN,” she captioned the playful video.

Last week, the “Euphoria” star nearly bared it all as she turned up the heat with another look from Syrn.

Her curves were on display as she donned the brand’s Fantasy lace halter bodysuit ($89) in a behind-the-scenes video from a photo shoot.

Earlier this month, she showed off some of her go-to pieces from the Jeff Bezos-backed brand via Instagram.

“On Syd’s Rack. From Syd’s boobs to yours, shop her favorite looks on SYRN.com ♥️” Sweeney cheekily captioned the post.

In the snaps, the 28-year-old modeled one design from each of her label’s four “worlds” — Seductress, Romantic, Playful and Comfy — and curated her most-loved looks for shoppers on the Syrn site.

She highlighted several lacy looks, including her favorite corset that she’s worn both out and about and on “Euphoria.”

Since launching her brand in January, Sweeney has been heavily involved in its marketing, often posing for pics in various skin-baring looks.

Last month, the actress’ boyfriend Scooter Braun supported her as she hosted a pop-up event for Syrn at Bigg Chill frozen yogurt shop in Los Angeles.