The XS Scuba HL515 Highland Plastic Book Screws are a simple, reliable way to secure and organize components on backplate-and-wing (BP/W) setups. These lightweight, non-corrosive plastic “book screws” (also commonly called Chicago screws / sex bolts) are ideal for divers who want an affordable alternative to stainless hardware for low-load attachment points—especially in wet, salty environments where rust is a concern.

Use the HL515 set to attach or tidy up common rig components like wings, single tank plates, accessory plates, or add-on items (ex: pouches or mounting tabs) where you want a clean, low-profile fastener that won’t corrode. Each screw set is designed to pass through standard mounting holes and helps keep your configuration secure and streamlined.

Highlights & Features

Non-corrosive durable plastic construction for long life in freshwater or saltwater

Will pass through a 3/8 in (9.5 mm) hole for broad compatibility with many plates/accessories

Includes 4 complete sets (male & female screw pairs) — great for spares or multiple attachment points

A practical choice for divers building or maintaining technical-style harness and BP/W rigs

Specifications (HL515)

Head diameter: 0.74 in (18.8 mm)

Shaft diameter: 0.36 in (9.1 mm)

Internal height: 0.35 in (8.9 mm)

Quantity: 4 complete sets