Collars and Couplings offers split collar/couplings in inch black oxide keyway/no keyway, inch stainless steel keyway/no keyway and metric black oxide no keyway.

Lucas Industrial has split couplings in double split oxide and stainless steel couplings. The double split oxide couplings range in length from 1 7/8" to 3 3/4", and the double split stainless couplings range in size from  1 7/8" to 3" in length.

Northeast Fasteners has a range of double split shaft couplings in stainless with/without keyway metric sizes, and black oxide with/without keyway metric sizes. Northeast also has a large selection of inch sizes for the black oxide couplings, available with and without keyway.

Dayton Superior Products has a two piece double split couplings, for changing (or servicing) a coupling without having to completely break down the shaft. The eight-socket screws allow for a greater load bearing operation than the single split version. The couplings are available in bore sizes from 1/4" to 2", and are available in stainless steel or black oxide.

Lovejoy has a standard curved-jaw coupling that's available as a clamping hub with a double slot system, and is available either with or without keyway. The coupling has a zero/minimum backlash, with a torque capacity dependent on bore size. The curved-jaw coupling has a failsafe system that's resistant to oil, sand, dirt and grease, and has no metal/metal contact.

Roller Chains 4 Less supplies double split shaft collars and other power transmission components. These double split collars are made from black oxide and come in sizes ranging from 1/4" to 3".