This is the muffler screw set for the #744B and E4020 OS Max mufflers. They are used to mount the muffler to the engine.
Features: Black steel construction
Includes: Two 4mm x 40mm cap-head mounting bolts (shouldered)
Specs: Cap-head screws feature a .7mm coarse thread
Note: A 3.0mm allen wrench is required for tightening the cap-head screws.