K2 Systems 4000170 Lag Screw 5/16 x 3" SS, W/ EPDM Washer- Pack of 24

K2 Systems Lag Screw 5/16 x 3" SS, W/ EPDM Washer

The Lag Screw 5/16" × 3" SS with EPDM Washer  is a stainless-steel roof-mounting fastener designed for securing solar mounting feet or brackets directly to structural rafters on pitched roofs, featuring a preassembled EPDM sealing washer that helps create a weather-resistant roof penetration while ensuring strong mechanical attachment.

• Model/Type: 4000170
• Pack of 24 units
• Finish: Mill
• Included Hardware: (1) Stainless-steel 5/16" × 3" lag screw+1 ×(1) Pre-assembled EPDM sealing washer
• Durable & Certified: The lag screw is manufactured from corrosion-resistant stainless steel and designed for long-term outdoor roof-mounting applications, providing durable structural fastening when installed into rafters or decking; as part of the K2 mounting system hardware, it supports assemblies tested to industry standards such as UL 2703–certified mounting systems, reflecting verified structural performance and long-term reliability.
• Water Protection & Fit: The screw is supplied with a pre-assembled EPDM sealing washer, designed to create a weather-tight seal at the mounting penetration point. EPDM rubber resists UV exposure, temperature changes, and moisture, helping prevent long-term cracking or leakage.