The colour-preserving (CP) semi-Snark is a period-multiplying colour-preserving signal conduit found by Tanner Jacobi in October 2017, producing one output glider for every two input gliders. It is made by replacing one of the eaters in a Snark with a catalyst found using Bellman. The catalyst causes the formation of a tub which requires a second glider to delete. However, this adds 5 ticks to the repeat time, so that it becomes 48. This is still 3 ticks faster than the CC semi-Snark.