HS-RK Tsurumi HS Series Sand KitHS RK Tsurumi HS Series Sand Kit Model Number: HS RK Residue Kit Item Price: $55. 00 Tsurumi HS RK residue kit for the Tsurumi HS2. 4S sand pump: An inexpensive option to our 1 2 hp HS Series pump, the residue kit allows you to pump down water to 1 4 of an inch. Simply remove the original strainer, nuts, and bolts and replace them with the residue plate and packaged hardware.