The iOptron CEM40 telescope mount ships with the 8407+ handset, but does not have a holder, so it just dangles with no place to attach it. To remedy this, I designed a holder for the handset that attached to the tripod leg (2 inch diameter). The two pieces fit together and are held in place with 1/4-20 x 1 inch bolts. Make sure to hand tighten only, which will keep the handset holder held solidly in place with a limited ability to move it up and down as well as side to side (I placed mine at the top of the tripod leg).
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