Great putter head that takes a standard .370 shaft (in expensive triple bend shaft linked below)

You'll need the following to finish it:

• Lead scuba weights: https://www.amazon.com/gp/product/B000XEJW8E/ref=pe_2313370_714093650_em_1p_0_lm?th=1&psc=1
• M5 x 8mm flat head socket screws: https://www.amazon.com/gp/product/B08HLT5BMS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
• M4 x 8mm flat head socket screws: https://www.amazon.com/gp/product/B089QTSSZH/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• Play sand: https://www.amazon.com/gp/product/B00TCM3YIC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Step 1 - Once it's printed, fill all holes with the lead weights, making sure to stuff as many weights as possible into the cavity

Step 2 - Fill the cavities with the play sand

Step 3 - Use the M5 screws for the main body holes

Step 4 - Use the M4 screws for the 2 “wing” holes

If you'd like a relatively inexpensive shaft to go along with it, that's linked here: https://www.valuegolf.com/apollo-black-triple-bend-putter-shaft