Jewell Amber Oil genuine rocker box grease in cartridges which fit all standard "large" grease guns. Click product for quantity discounts. Remember to get a few of the 11oz "tubes" as well, since the (Alemite, or zerk) grease fittings on the heads do not serve the valve guides, nor rocker arm rollers, valve tips or pushrods, on many applications.
If using in a conventional grease gun, this stuff will prove messy: Be sure to relieve the tension from the plunger below the grease when not in use, store grease gun with plunger end upward, and hope for the best
For bulk users (regular flyers), quantity discounts available: see below item listing. Also, we now carry a small non-leaky oil gun to carry onboard the airplane.